Challenges and Drivers for the Adoption of Improved Solar Drying Technologies in Mango Farming: A Case Study of Smallholder Farmers in Mozambique

Abstract

Mango production plays a vital role in rural livelihoods in Mozambique, yet post-harvest losses remain high, ranging from 25% to over 50%, due to inadequate preservation methods. Improved solar drying technologies offer a sustainable solution by extending shelf life and enhancing product quality. However, their adoption among smallholder mango farmers remains limited. This study investigates the key barriers and drivers influencing the uptake of these technologies in three districts of Inhambane Province, through a combination of literature review and semi-structured interviews. Major barriers include limited technical knowledge, high upfront costs, poor market access, and limited institutional support. Field data show that over 80% of farmers are unaware of improved fruit drying techniques, and fewer than 5% have received any training. While the literature emphasizes environmental sustainability and policy support, field interviews highlight a stronger interest in practical enablers, such as affordable systems, hands-on training, and income-generating potential. The study calls for a multisectoral approach, involving financial support, capacity-building, and strengthened extension services to promote adoption. Scaling solar drying technologies can significantly reduce post-harvest losses and strengthen the mango value chain, contributing to food security and rural development in Mozambique.

1. Introduction

Mango is one of the most important tropical fruits globally, accounting for over half of total tropical fruit production and ranking as the most widely consumed fresh fruit worldwide [1]. The fruit tree can be found in various regions, with production occurring in 115 countries, primarily in developing countries. In sub-Saharan Africa, mangoes serve not only as a vital crop but also as a source of income, contributing to the reduction in farmers’ poverty [2]. In Mozambique, mango is the second most produced fruit, predominantly cultivated by small-scale farmers [3]. The country’s tropical to subtropical climate, with abundant sunshine and extended dry seasons, offers favorable conditions for solar-based preservation methods, particularly solar drying. These natural climatic advantages make solar drying not only practical but potentially cost-effective for smallholder farmers, assuming the right technologies and support systems are in place.

However, despite its significance and widespread cultivation, mango production in Mozambique faces serious challenges, such as high post-harvest losses, ranging from 20% to 40% [4]. During peak harvesting season, when local demand is surpassed by market surpluses and preservation infrastructure falls short, these losses can exceed 50% due to the use of insufficient and inadequate preservation techniques [5,6].

In the absence of modern infrastructure, many farmers rely on traditional sun drying to preserve their harvest. Traditional sun drying is a popular and effective post-harvest method, especially in low-income countries, for drying and preserving agricultural products [7,8,9]. It consists of crops being typically spread on surfaces such as the ground, mats, or cement floors, where they are exposed to solar radiation for a significant portion of the day while also benefiting from natural air circulation to facilitate drying. This method of drying products is commonly used in Africa for drying staple foods [10,11]. However, it encounters several drawbacks, starting with the risk of product quality degradation due to possible contamination, often caused by insects, pests, animals, wind-blown debris, and rain [12]. Additionally, drying parameters such as drying flux, heat input, temperature, and moisture content cannot be effectively controlled [7], resulting in inconsistent drying and product loss.

To combat this issue, the introduction of improved solar dryers (solar dryers with advanced designs that enhance drying efficiency, preserve the product quality, reduce contaminations, and offer better protection against environmental factors such as pests, rain, and dust, and lead to longer shelf life) presents a promising solution. Improved solar dryers utilize solar energy like traditional methods, but offer faster drying, better hygiene, and reduced contamination [8,9]. The difference is that an improved solar dryer offers faster drying and better product quality. Different designs for improved solar dryers have been described over the years (see, for example, [13,14,15,16,17,18]). The literature shows that although designs may vary, they consistently share key benefits.

Improved solar dryers are typically enclosed systems that enhance efficiency by trapping heat and increasing airflow, reducing drying times by 30–60% and achieving drying rates two to three times faster than traditional open-sun methods [8,19]. They also improve hygiene by protecting products from dust, insects, and rain, thereby lowering microbial growth and contamination risks [8,19]. Indirect models provide stable temperatures (40–70 °C) while minimizing UV exposure, which helps preserve nutrients, color, and aroma [8]. Hybrid solar dryers offer additional reliability by allowing real-time adjustments, further reducing spoilage and post-harvest losses [9]. This technology has the potential to mitigate persistent post-harvest losses in Africa by transforming surplus fresh mangoes into shelf-stable products, thereby enhancing year-round food availability and contributing to food and income security. The commercialization of mangoes presents substantial opportunities for improving farmers’ livelihoods.

Nevertheless, despite these advantages and the clear potential of solar drying to reduce losses and improve incomes, the actual adoption of this technology remains limited. Several factors hinder producers from fully utilizing solar drying technologies, even in regions where mangoes are abundant and post-harvest losses have significant economic implications [7,11]. Understanding the barriers to adoption is therefore critical to unlock the potential of solar drying as a sustainable post-harvest solution [10]. This study addresses that gap by using a literature review and semi-structured interviews with local farmers and agricultural extension officers.

This study aims to identify and analyze the key challenges that hinder the adoption of improved solar drying technologies, as well as the drivers that facilitate their use among smallholder farmers in Mozambique. Ultimately, the goal is to guide strategies that enhance uptake and improve post-harvest management practices. This research will explore the feasibility, scalability, and cultural acceptance of improved solar drying technologies as sustainable post-harvest interventions.

2. Materials and Methods

2.1. Literature Review

A systematic review of scientific literature was conducted to identify the key barriers and drivers influencing the adoption of solar dryers in Africa. The review focused on studies that examined both the challenges and enabling factors affecting the uptake of solar drying technologies. Literature searches were performed using Google Scholar, Web of Science, and Scopus using the following keywords: ‘adoption of solar drying’, ‘barriers’, ‘challenges for adoption’, along with ‘fruits’, ‘agricultural produce’, and the names of specific African countries. Duplicate records were removed to ensure the accuracy of the dataset. The findings were synthesized and presented in summary tables.

2.2. Interviews

Geographical Area of the Study

Mozambique, located in the southeast region of Africa, has 10 geographic provinces, and mango is produced in all of them. This study focuses on the Inhambane province (Figure 1, left panel), known for high mango production, and three specific districts: Morrumbene, Jangamo, and Inharrime (Figure 1, right panel), where the interviews took place.

2.3. Data Collection

A semi-structured interview was conducted with smallholder farmers who produce mango in the three abovementioned districts of the Inhambane province. The interview combined socio-economic data with farmers’ agricultural practice activities as well as their familiarity with improved solar dryers. This information helped identify financial capacity and decision-making dynamics that influence farmers’ willingness and ability to invest in new technologies, clarify where solar drying could add value or improve food security, while providing insights into knowledge gaps, training needs, and cultural acceptability of the technology. Additionally, information about the production level and post-harvest losses was also collected to quantify the scale of the problem that solar drying could address. Complementary interviews were conducted with agricultural extension officers from each of the three districts. These stakeholders provided broader perspectives on agricultural support and potential technology adoption pathways. These highlighted the level of institutional support and training infrastructure available, while assessing the readiness for the adoption of solar dryers. The study utilized a convenience sampling strategy, as described by [12], selecting farmers who were easily accessible, resided near the village, were available during the interviews, and were willing to participate [20]. This approach supported efficient data collection, given logistical constraints in reaching more remote areas. However, as farmers in those regions may differ in certain practices or perspectives, the findings may have limited applicability across the broader farming population.

A total of 72 individuals were interviewed, distributed across three districts: 20 in Inharrime, 23 in Jangamo, and 29 in Morrumbene. This sample size was deemed sufficient for this exploratory study, given its focus on context-specific analysis rather than statistical generalization. Participants included both men and women, representing farmers from various socio-economic backgrounds.

2.3.1. Biographic Data

For ethical purposes, verbal consent was obtained prior to the beginning of the interviews. The interviewee was provided with details about the purpose of the research and comprehensive information about the study, allowing them to make an informed decision about their participation. Participants were also informed about the freedom to refuse to answer the questions and withdraw the questionnaire at any time. Questions related to family size and the number of adults and children in the household were included to better understand the influence of house structure on the adoption of the improved solar dryers. This aligns with the Sustainable Livelihoods Framework [21], which emphasizes human capital, including household composition, as a key determinant of livelihood strategies and agricultural productivity, as well as the adoption of technologies.

2.3.2. Baseline Farming Conditions

To gather information related to farming conditions, each interviewee was asked questions about the farm size and farming time, as well as the land type and the use of agricultural inputs.

2.3.3. Mango Farming Profile

Questions related to the main fruits produced by the interviewees, including the mango cultivars used, and their production and losses, were asked. Also, aspects related to the perceived reasons for the production losses, the places where the production was commercialized, and other sources of income were addressed.

2.3.4. Familiarity with Solar Drying Technology

The interviewees were asked about their familiarity with drying technologies, their use of preservation methods, and their existing knowledge of drying techniques. The discussions also explored any training they had received, their opinions on the most relevant fruits to dry, the perceived benefits of using improved solar dryers, and their willingness to invest in a solar dryer. Participants were also questioned about the market for dried fruit and their perceptions of the barriers to adopting improved solar dryers.

2.3.5. Interview with Agricultural Extensionists

A total of 21 agricultural extension technicians were interviewed, with equal representation from the districts of Inharrime, Jangamo, and Morrumbene. The interviews focused on various aspects of fruit production, particularly mangoes, within the local agricultural context. Key topics included available support services, major production challenges, and income comparisons with other high-value crops. Additionally, the discussions explored government and NGO initiatives aimed at boosting mango production, strategies to improve market access, and recent changes in conservation practices.

2.4. Prioritization of Barriers

To establish a priority order among the identified barriers, a semi-quantitative scoring approach was employed. Interview-derived frequencies were first normalized to a 0–100 scale and grouped into four domains—Knowledge, Awareness, Finance, and Technical—based on conceptual coherence and previous adoption studies [22]. Within each domain, indicators were aggregated using equal weighting, as no empirical evidence justified differential weights, and equal weighting offers a transparent and reproducible baseline for comparison.

Composite severity scores for each domain were then used as input to a compact Analytic Hierarchy Process (AHP)-style prioritization. This simplified version of AHP avoids exhaustive pairwise comparisons by directly ranking domains according to their composite severity scores, an approach recommended for semi-quantitative data derived from field interviews [23].

To test the robustness of the resulting ranking, we conducted a sensitivity analysis by varying input frequencies by ±10%. The analysis preserved the relative order of the top three domains, supporting the stability of the prioritization outcomes.

3. Results

3.1. Insights from the Literature—Challenges and Drivers for the Adoption of Solar Dryers Among Smallholder Farmers in Sub-Saharan Africa

Although the literature search was not time-restricted, the search tools returned results only from 1987 onward. Our search yielded a total of 204 articles. After removing duplicates and filtering out articles that did not contain the relevant search terms, 31 studies that critically analyzed the challenges and drivers affecting the adoption of solar dryers in Africa were identified. Between 1987 and 2024, a total of 31 scientific papers were published addressing the challenges and drivers linked to the adoption of solar drying technologies in Africa.

The literature review revealed a wide range of factors influencing adoption, as categorized by various authors. However, most studies focused on solar dryers in general, without distinguishing the type of food being dried. Only three studies specifically addressed improved solar dryers for fruits [16,24,25], and just one focused on mangoes [25], despite mango being among the most consumed fruits in Sub-Saharan Africa and Mozambique. This is notable given its significant nutritional value, particularly for youth and rural communities facing deficiencies in essential vitamins and minerals.

The key challenges included high initial investment costs and limited access to financing [2,26]; lack of technical skills for operation and maintenance [27,28]; and cultural resistance to new technologies [26,29,30], particularly where traditional drying methods are well-established. Additionally, insufficient awareness or understanding of how improved solar dryers function may lead to scepticism among farmers, further hampering adoption [5,28].

Inadequate policy support and lack of standardization [2], limited drying capacity and performance of existing systems [31,32], and infrastructure limitations such as unreliable electricity and poor transport networks, also present significant barriers [5]. Moreover, variable weather patterns across regions mean that solar drying cannot always be relied upon without complementary methods, which complicates consistent use. Concerns over the marketability and access for solar-dried products were also reported [5,33].

Table 1. Challenges for the adoption of Improved solar dryers.

Category	Challenges	Total Articles	References
Technical	Lack of technical skills/knowledge, infrastructure constraints and weather issues, maintenance and design complexity, and limited local fabrication or access	26	[5,13,14,15,17,19,25,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45]
Financial	High initial investment costs	20	[5,13,19,25,27,28,29,30,32,34,35,36,37,38,40,42,44,45,46,47]
Socio-cultural	Low awareness and cultural resistance to adoption/widely accepted traditional practices	15	[5,13,14,15,19,24,26,28,29,31,32,34,35,44,45]
Institutional	Inadequate policy support/lack of R&D	7	[13,14,27,28,34,35,45]

summarizes the key challenges for the adoption of improved solar dryers identified in different studies.

The adoption of improved solar dryers in African regions is driven by several key factors, primarily the abundant solar energy available, which positions solar drying as a viable and sustainable option [14,24,39,40]. There is a critical need to reduce post-harvest losses and enhance the quality of dried products, spurring the search for efficient and affordable drying technologies [13,40,42]. Furthermore, utilizing locally available materials for the construction of improved solar dryers boosts accessibility and sustainability for rural communities [34].

Farmers exhibit significant enthusiasm for embracing improved solar dryers, especially when these systems are efficient and affordable. Many express a desire for commercialized solutions that allow payment per unit of dried products, showcasing a readiness to explore market-based options [43,45]. The appeal of improved solar dryers is also reinforced by their ability to improve product quality, reduce drying times, and enhance overall drying efficiency [19,35,43]. Importantly, recent technical advancements have enabled efficient drying processes that do not rely on grid electricity, making these systems especially suitable for remote, off-grid rural areas where energy access is limited.

In some countries, support from governments and international collaborations offers crucial technical and financial assistance for the implementation of these technologies [25,44]. Additionally, involving the community in the design and implementation of solar drying systems fosters greater acceptance and ensures that these innovations align with local needs [25,29]. The intersection of environmental sustainability, improved product quality, market access, and comprehensive training and support for farmers drives the growing adoption of improved solar dryers.

Table 2. Drivers for the adoption of improved solar dryers.

Category	Drivers for the Adoption	Total Articles	References
Environmental	Abundant solar radiation in Africa/Environmental sustainability goals	21	[13,15,17,19,25,26,27,28,32,34,35,36,37,38,39,40,41,42,43,44,45]
Economic	Need to reduce post-harvest losses	20	[13,17,22,23,25,26,27,28,32,34,36,37,38,39,40,42,43,44]
Institutional	Government and NGO support	9	[14,22,23,26,27,28,31,36,42]
Market	Growing demand for dried products	7	[13,29,31,32,34,38,43]
Technical	Improved product quality through technological advancements	6	[15,16,30,34,41,44]
Energy	Energy independence in off-grid rural areas	4	[15,25,26,35]

summarizes the most cited drivers for the adoption of improved solar dryers identified in the performed literature review.

A comparison between Table 1 and Table 2 suggests that adoption is not limited by lack of perceived value, but rather by the capacity to overcome practical and systemic barriers. It is noteworthy that institutional support appears in both Table 1 and Table 2, as a barrier when lacking, and as a driver when present and effective. This reflects the critical role of enabling environments, where targeted government or NGO interventions can significantly shift adoption outcomes.

3.2. Field Interviews—Mango Production as a Contextual Case for Adoption Challenges and Opportunities

To contextualize these general findings from the literature, we conducted field interviews in southern Mozambique, focusing on mango production—a crop that illustrates both the urgency and potential of adopting solar drying technologies. This approach provides a concrete lens through which broader solar drying adoption dynamics can be understood.

Mango presents a compelling entry point for promoting solar drying technologies due to its high production and loss rates, cultural and nutritional value, seasonal glut, market volatility, and strong presence in household diets.

Improving mango preservation through solar drying could simultaneously reduce food waste, stabilize income, and enhance nutritional outcomes, especially given mango’s role in provitamin A intake. This localized use case supports the broader literature’s assertion that solar drying can contribute to food security and economic empowerment when aligned with community-specific needs.

The existing literature often overlooks the influence of household structure and labor dynamics on the adoption of post-harvest technologies. By capturing household size, gender roles, and land ownership patterns, the following findings provide important context for understanding who makes technology-related decisions and who implements them.

3.2.1. Demographic Profiles and Agricultural Practices

Family size and farm size are important since agricultural practices are mainly characterized by dependence on family labor. Interviews with farmers revealed that both men and women are actively involved in farming activities to support their families.

Table 3. Biographic data of the interviewees.

Collected Data	Districts
	Inharrime	Jangamo	Morrumbene
Biographic data
Number of interviewees	20	23	29
Female (%)	25	26	59
Male (%)	75	74	41
Family size (members) (%)
0–5	15	39	38
5–10	55	48	62
10–15	20	13	-
>15	10	-	-
Number of adults (%)
0–5	90	91	100
5–10	10	9	-
10–15	-	-	-
Number of children (%)
0–5	35	78	90
5–10	55	17	10
10–15	10	4	-

shows that the majority of the interviewees in Inharrime and Jangamo districts were male (75% and 74%, respectively), while in Morrumbene district, only 41% were male.

Demographic data of the interviewed farmers also showed that most of the farmers have families with 5 to 10 members. In all three districts, approximately 90% of families or more have 0 to 5 adult members, but when it comes to the number of children, Jangamo and Morrumbene districts have more than 50% of the families with 0 to 5 children. In the Inharrime district, 10% of the interviewed farmers reported having more than 10 children (see Table 3), which was attributed to the common practice of living with both their own children and grandchildren due to cultural and economic factors in the region.

The agricultural practices illustrate how these activities occupy the farmers and their willingness to engage in additional activities, such as solar drying of agricultural produce. Figure 2 illustrates the agricultural practices in each district. In all districts, the farmers produce almost all of their food, cultivating between 0 and 5 hectares of land. This has been reported in previous agricultural studies as the typical farm size for small-scale agricultural farmers in Mozambique [48]. The Jangamo and Inharrime districts, however, reported a different situation. While in Jangamo districts, 17% of the interviewees cultivated 5 to 10 hectares of land; the figure was higher in Inharrime, with 45% of the interviewees reporting the same areas. Additionally, in the Inharrime district, 15% of the interviewees reported managing more than 15 hectares of land for agriculture, which classifies them as medium-scale farmers [48].

Most of the reported agricultural production is a double-purpose crop, with parts used for consumption and the rest sold to generate income, crucial for their economic stability. Additionally, a minority of interviewees (30% in Jangamo and 10% in Morrumbene) reported having a car or other means to transport their agricultural goods to the market and provide some services needed by their families.

Although some studies identify mango as a high-yield but under-commercialized crop in Sub-Saharan Africa [49], few provide localized insights into how production translates into income or loss. This section explores those dynamics in southern Mozambique, revealing both the potential and the vulnerabilities of mango as a livelihood source.

3.2.2. Exploring the Impact of Mango Production on Farmer’s Income

Mango production plays a central role in the agricultural systems of Inharrime, Morrumbene, and Jangamo districts in southern Mozambique. Inharrime and Morrumbene districts are characterized by a high prevalence of mango cultivation, with 85% and 59% of farmers growing the fruit, respectively. In contrast, the Jangamo district has a more diversified fruit production, with 61% of farmers also growing guava and graviola alongside mango. On average, households in these districts produce approximately two tons of mangoes per harvest season. The dominant cultivar across Jangamo and Morrumbene is the local “Pink Mango”, while commercial cultivars such as “Tommy Atkins” and “Kent” are more common in Inharrime and Jangamo.

Over the past five years, production volumes have increased; however, the overall contribution of mangoes to household income remains limited. This is mainly due to persistent market constraints, significant post-harvest losses, and widespread fruit fly infestations.

In Inharrime, only 5% of producers rely on mango sales for income, compared to 39% in Jangamo and 55% in Morrumbene. During the peak harvest season from December to February, mangoes are typically sold for 10 to 12 Mozambican meticais (Mts) (approximately 0.16 to 0.19 USD) per kilogram. However, market conditions are highly volatile, and returns are often low. A major factor undermining profitability is the high level of post-harvest losses, which range from 25 to 50% in Inharrime to over 50% in Jangamo and Morrumbene. These losses are attributed to inadequate preservation infrastructure, poor post-harvest handling practices, and limited access to formal markets. Similar findings have been reported by [50,51,52], which highlighted the critical issue of fruit loss.

Farmers rely on multiple marketing channels to sell their mangoes. Local markets are a common outlet, used by 25% of farmers in Inharrime and 31% in both Jangamo and Morrumbene. In addition, small agricultural cooperatives in Inharrime and Jangamo facilitate collective sales. A notable informal system involves “maguevas,” women from nearby towns who buy mangoes in bulk directly from farmers and resell them in urban centers. This localized, community-based approach offers a flexible but limited means of accessing markets. As a result, many producers opt for alternative crops, like pineapples, which offer more consistent support, including immediate payments and transportation facilitated by local processing companies like AFRIFRUTA.

Table 4. Mango farming profile: varieties, production, and losses.

Collected Data	Districts
	Inharrime	Jangamo	Morrumbene
Fruits Production
Households engaged in fruit production (%)
Citric fruits	10	22	21
Banana	5	4	3
Avocado	-	9	14
Papaya	85	4	59
Other local fruits	-	61	3
Mango production (ton) (%)
2	85	83	79
3	10	13	14
4	5	4	7
Used mango cultivars
Tommy Atkins	15	13	4
Kent	-	4	-
Pink mango (manga rosa)	-	65	86
All of the above varieties	85	18	10
Mango as a source of income (%)
Yes	5	39	45
No	95	61	55
Mango production losses (%)
0–25	25	13	7
25–50	55	48	48
>50	20	39	45
Reasons for Post-Harvesting Losses
Poor harvesting technology	-	4	3
Poor post-harvesting technology	10	17	17
Lack of preservation facilities	20	35	80
Other reasons	70	44	-
A place to sell mango production (%)
In the local markets	25	31	31
Via the middlemen	-	-	17
Through a cooperative/collective market	5	21	-
Other	70	48	52

summarizes the key aspects of mango farming across the three districts, indicating the grown cultivars, the level of farmers’ engagement in mango production, and the extent of post-harvest losses encountered.

Despite their limited commercial appeal and beyond income generation, mangoes continue to represent an important component of household diets. Families consume large quantities during the harvest season, but the seasonal glut often leads to consumption fatigue. The excess fruit is frequently repurposed as animal feed, highlighting the inefficiencies in the current mango value chain. While mangoes provide a seasonal income stream, their economic viability is constrained when compared to pineapples, which are generally more profitable and less perishable, as also shown by [6].

The underdevelopment of the mango sector can be attributed in part to insufficient strategic support from agricultural extension services, which often tend to prioritize staple crops. Technical assistance is sporadic and limited in scope, focusing primarily on basic cultivation practices without addressing critical aspects such as post-harvest handling or value addition. Financial support is minimal, and training opportunities are not systematically delivered. Although private sector initiatives such as those led by local processing companies like KUVANGA and AFRIFRUTA have helped improve producer organizations and market access, their impact is currently insufficient to generate a large-scale impact.

Results from the interviews with the agricultural extensionists in the three districts revealed that mango production in the districts is a vital yet underdeveloped part of the agricultural landscape, primarily characterized by small-scale farming and a lack of formal structure. While many farmers grow mangoes, the support they receive is often reactive and limited to those who actively seek assistance from extension officers. The focus of agricultural extension tends to prioritize staple crops such as cassava, peanuts, and beans, leaving mango producers with insufficient resources and guidance. This lack of strategic planning has resulted in significant production losses, primarily due to pest issues like fruit flies and inadequate market opportunities. Although there are some success stories, such as farmers organized in agricultural associations supplying mangoes to AFRIFRUTA, a local company that dries fruit for export to Europe, the overall market for mangoes remains weak, with no established processing industries to absorb the surplus.

To improve the situation, there are various forms of technical support available, including training on good agricultural practices and pest management. However, the effectiveness of these programs is hindered by limited access to essential inputs, like pheromones for fruit fly control, and a lack of processing capacity, which leads to high levels of spoilage. While initiatives have been introduced to enhance mango production, such as the creation of cooperatives and partnerships for mango purchases, the financial viability of mango farming remains low compared to other high-value crops. For mango production to thrive, there is a pressing need for more comprehensive strategies that connect producers to profitable markets, enhance processing capabilities, and provide ongoing support to ensure sustainability and competitiveness in the agricultural sector.

To realize the full potential of mango production, a coordinated investment in the value chain is essential. This includes expanding and enhancing access to appropriate post-harvest technologies, improving infrastructure for storage and transportation, strengthening farmer organizations, and promoting the use of affordable processing methods such as solar drying. These interventions would help reduce losses, enhance product quality, and increase market competitiveness, ultimately transforming mango production into a more stable and profitable livelihood strategy for smallholder farmers in southern Mozambique.

The literature outlines financial, technical, and institutional barriers to the adoption of solar drying technologies across Africa [25,26,27,28]. The field interviews confirm many of these challenges but also highlight district-specific nuances, especially in terms of willingness to invest, perceived benefits, and cultural familiarity with drying practices. The following section dissects these barriers and drivers in greater detail.

3.2.3. Exploring Challenges and Opportunities for the Adoption of Solar Drying Technology in Mango Preservation

Table 5. Knowledge, preferences, and market perceptions on solar-drying technologies.

Collected Data	Districts
	Inharrime	Jangamo	Morrumbene
Drying Technology
Familiar with improved technologies for fruit drying? (%)
Yes	-	-	-
No	100	100	100
Use of preservation methods (%)
Yes	5	4	3
No	95	96	97
Existing knowledge about drying mango (%)
No knowledge	85	87	83
Some knowledge	15	13	17
Received any training about drying fruits? (%)
Yes	5	4	-
No	95	96	100
Ever bought dried mango? (%)
Yes	50	4	-
No	50	96	100
Ever dried mango? (%)
Yes	10	4	-
No	90	96	100
What is the main benefit of using a solar dryer system for fruits? (%)
Preservation of the fruit	25	44	66
Quality of the dried fruit	-	4	3
Economic drying system	-	4	18
Source of income	-	18	10
All of the above	75	30	3
How much are you willing to invest in a solar dryer system? (Mts) (%)
0–5000	40	30	69
5001–10,000	35	35	31
10,001–15,000	10	9	-
>15,000	15	26	-
What main aspects to consider when investing in a solar dryer system? (%)
Investment cost	85	30	69
Drying time	-	9	-
Drying capacity	-	9	-
Flexibility in use	5	26	-
All of the above	10	26	31
Would there be a market for dried fruits? (%)
National market	5	-	-
Local market	95	91	76
Both national and local markets	-	9	24
Awareness of NGOs or government initiatives promoting solar drying of fruits? (%)
Yes	-	9	-
No	100	91	100
What are the main barriers to using improved solar dryers in the village? (%)
Lack of money	-	9	-
Lack of knowledge	15	61	59
Both lack of money and knowledge	85	30	41

reports data on the familiarity, use, and perceptions of improved drying technologies for fruits, particularly mangoes, across Inharrime, Jangamo, and Morrumbene. Multiple interrelated challenges hinder the adoption of solar drying for mangoes, particularly limited technical awareness and financial capacity [51].

Interviews revealed that respondents across Inharrime, Jangamo, and Morrumbene are largely unfamiliar with improved drying technologies. This lack of awareness limits the adoption of these technologies, which could significantly improve the quality and shelf life of dried mangoes. Most respondents also lack basic knowledge about drying mangoes, and formal training opportunities are extremely limited, reported by only 5% in Inharrime, 4% in Jangamo, and none in Morrumbene. This widespread knowledge gap is consistent with previous findings in Africa, where limited technical capacity and the absence of training programs significantly hindered the uptake of improved solar dryers [27,28,29,53]. Barriers to adoption identified in Jangamo and Morrumbene centred on insufficient knowledge (61% and 59%, respectively), while in Inharrime, both knowledge gaps and affordability were cited. These findings highlight the critical need for educational programs to develop local expertise alongside financial support as part of a broader technology refinement and dissemination effort.

The minimal use of traditional solar drying methods, with only 5% of respondents in Inharrime, 4% in Jangamo, and 3% in Morrumbene, further restricts the baseline familiarity needed to adopt improved technologies. This diverges from contexts in other African regions where traditional sun-drying is culturally entrenched [26]. The absence of such practices in Mozambique suggests that solar drying may require more intensive awareness-building and behavioral change strategies. This indicates that the use of improved solar drying is not widely practiced, which further limits the potential to maintain fruit quality. Therefore, increasing the use of solar conservation methods could significantly enhance the shelf-life and quality of mangoes [53,54].

In terms of market engagement, 50% of respondents in Inharrime have purchased dried mangoes, though only 10% have dried mangoes themselves, often out of curiosity rather than as a method of conservation. The practice is even less common in Jangamo and Morrumbene, suggesting limited practical experience with the drying process in these regions.

Cost has been consistently cited in the literature as the most significant deterrent to adopting solar drying technologies [13,16,40]. In line with this, financial concerns dominated responses in all three districts, though levels of investment willingness varied, suggesting that income level, market orientation, and past exposure to technology all play roles.

Affordability was consistently identified as a key barrier to adopting solar drying technologies, particularly in Morrumbene (69%), followed by Inharrime (40%) and Jangamo (30%). These figures reflect a broader pattern observed across Sub-Saharan Africa, where the high upfront costs of improved solar dryers remain a persistent constraint [7,13,55]. Even when farmers recognize the benefits of the technology, their ability to invest is often curtailed by low household income, small production volumes, and weak integration into formal markets. Differences between districts may also reflect varying degrees of market orientation and exposure to external support services. These findings underscore the need for targeted financial mechanisms such as subsidies, microcredit schemes, or cooperative purchasing models to make improved solar dryers more accessible for smallholder farmers.

Although there are variations in willingness to invest, respondents in Inharrime and Jangamo are more willing to invest above 5000 Mts (approximately 80 USD) compared to those in Morrumbene, which highlights the importance of financial support mechanisms. Financial interventions such as microcredits and subsidies may need to be tailored geographically, with a focus on the most resource-constrained regions. Addressing these cost-related challenges is crucial for enabling broader adoption of solar drying systems, as echoed by [56].

In addition to financial concerns, other factors relating to technological development and design, such as drying time, capacity, and flexibility, are considered, though to a lesser extent. These factors are more valued in Jangamo (26%) and Morrumbene (31%) than in Inharrime (10%), indicating the need for cost-effective, versatile, and efficient drying solutions.

These findings underscore the importance of addressing financial barriers and reducing upfront costs to promote the adoption of solar dryer systems. The need for cost-effective drying solutions was also mentioned as a key factor for the adoption of improved solar dryers in India [56,57]. Making renewable technologies such as solar systems more affordable is crucial for encouraging broader acceptance, particularly in rural communities [56]. By ensuring affordability, renewable energy projects can contribute significantly to sustainable development and empower local communities economically.

General perceptions of the benefits of solar dryer systems vary across districts. In Morrumbene, 66% of respondents recognize the conservation benefits, while 44% in Jangamo and 25% in Inharrime share this view. These conservation benefits included post-harvest losses reduction, food preservation, and environmental sustainability. Other benefits, such as improved storability, economic efficiency, and income generation, are acknowledged less frequently. Notably, 75% of respondents in Inharrime see a combination of all these benefits, compared to much lower recognition in Jangamo (30%) and Morrumbene (3%). Therefore, promoting the comprehensive benefits of solar drying systems, such as food preservation, cost savings, and environmental sustainability, could also enhance adoption rates [7,58].

Most respondents identified only a local market for dried mango products, with minimal awareness of national or regional demand. This limited market orientation aligns with findings by [59], who reported that smallholder farmers often lack the information and support needed to integrate into broader food markets, thereby reducing the incentive to invest in value-added processing technologies. While this may suggest a narrow market perspective among producers, it could also reflect the reality of limited and underdeveloped market channels beyond the local level. The lack of access to information, infrastructure, or reliable buyers at a larger scale may discourage producers from envisioning or pursuing broader markets. Therefore, the issue appears to be both a constraint of perspective and a reflection of genuine market limitations. Expanding market access and improving visibility of external demand could significantly enhance the economic viability of dried mango production and justify greater investment in solar drying technologies [59]. At the same time, increased local consumption of dried mango could contribute to improved nutritional outcomes, particularly in addressing vitamin A deficiency among children. Promoting the health benefits of dried mango and strengthening local demand could create dual benefits for livelihoods and community health. The sale of mangoes also contributes to food security by providing families with income to purchase other essential food items, highlighting the need for a balance between commercialization and local consumption to improve overall nutrition in the studied districts.

While institutional support, particularly from government and NGOs has been framed as a critical enabler in the literature [25,29,30] there are currently few, if any, government or NGO-led initiatives supporting solar drying in these districts; none were reported in Inharrime and Morrumbene, and only minimal activity was noted in Jangamo, where 9% of interviewees mentioned the existence of NGO initiatives to promote solar drying. This lack of institutional support limits access to training, technical assistance, and financing, all of which are crucial for the successful adoption of solar drying technology [13,57,60].

To quantitatively prioritize measures, we converted interview-derived frequencies into 0–100 severity scores by averaging aligned indicators within each domain. The knowledge domain combined no training (97%), lack of awareness of improved dryers (100%), and lack of fruit-drying know-how (97%). The awareness domain combined a lack of NGO/government initiatives (97%), a lack of practical exposure (94%), and local-only market awareness (87%). The finance domain combined district-weighted affordability barriers (48.5%) and unwillingness to invest above 5000 Mts (67%). The technical domain combined field salience (22%) with the frequency of design/time/capacity concerns in the literature (84%). This yielded composite severities of 98 for Knowledge, 93 for Awareness, 50 for Finance, and 53 for Technical. With these scores, we applied a compact AHP-style prioritization to rank intervention measures [61,62].

Thus, knowledge and awareness clearly emerge as the highest-priority domains, supported by multiple high-frequency indicators. Robustness was verified through sensitivity analysis (±10% on input scores), which preserved the ranking of the top three measures.

Figure 3a shows the severity scores (0–100) derived from field data and literature, highlighting the dominant role of knowledge and awareness gaps compared to financial and technical factors. Figure 3b compares the priority weights obtained through a simple normalized index and the Analytic Hierarchy Process (AHP) using the geometric mean method, both of which confirm the higher priority of addressing knowledge and awareness relative to finance and technical constraints. Figure 3c presents a sensitivity analysis (baseline weights), demonstrating that the overall ranking of measures is robust to variations of ±10% in individual severity scores.

Together, the analysis quantitatively reveals that interventions focusing on capacity building and awareness raising, supported by financial mechanisms, should be prioritized to accelerate the adoption of improved solar drying technologies.

To synthesize insights, the following section directly compares the themes emerging from literature with the realities documented in field interviews, highlighting convergence as well as context-specific gaps.

3.2.4. Comparative Analysis of Literature and Field Findings on the Adoption of Solar Drying Technologies

The results of the literature review and field interviews reveal significant overlap as well as key differences in the challenges and opportunities surrounding the adoption of solar drying technologies among smallholder farmers in Sub-Saharan Africa, particularly in the Mozambican context.

• Financial barriers

Both the literature and the field data emphasize high initial investment costs as one of the major obstacles to adoption. In the reviewed studies, this was cited as the second most dominant challenge across various African countries (Table 1). This pattern was echoed in the interviews, where respondents in all three districts, especially Morrumbene (69%), identified cost as a primary barrier, with only a small proportion willing or able to invest over 5000 Mts (approximately 80 USD) (

Table 6. Comparison of literature and field interview findings on the adoption of solar drying technologies.

Factor	Literature Findings	Field Interview Findings (Mozambique)	Alignment
Financial Constraints	High investment cost as a major barrier	Cited as a major barrier, especially in Morrumbene (69%)	Strong alignment
Technical Knowledge and Skills	Lack of technical know-how, low awareness	>80% unfamiliar with drying techniques; <5% received training	Strong alignment
Institutional Support	Need for government/NGO support highlighted	Minimal or no reported support from NGOs/government in most districts	Misalignment
Cultural Acceptance	Cultural resistance mentioned as a barrier in some regions	Not identified as a major issue in local interviews	Divergence
Perceived Benefits	Improved quality, efficiency, and income generation cited as drivers	Perceived benefits vary greatly; higher awareness in Inharrime than Morrumbene	Partial alignment
Market Access	Emphasis on growing demand and export potential	Local market seen as main outlet; limited knowledge of broader market opportunities	Misalignment
Use of Traditional Drying	Traditional drying methods are common and culturally entrenched	Very limited traditional drying practice (only ~5% use solar drying methods)	Divergence
Willingness to Invest	Financial incentives can improve adoption	Willingness present but varies; Inharrime more open to higher investments	Partial alignment

). This alignment underscores the critical need for financial support mechanisms, such as microcredit schemes or subsidies, to promote adoption.

• Technical knowledge and awareness

The literature frequently cited a lack of technical skills and awareness as a barrier to adoption (Table 1). Field interviews reinforced this, with more than 80% of respondents across districts reporting no knowledge of fruit drying techniques and less than 5% having received formal training (Table 5). This suggests that while the issue is widely recognized in academic discussions, it remains a persistent gap at the community level in Mozambique. The lack of familiarity even with traditional drying methods further highlights the need for educational outreach and training.

• Institutional support

While the literature pointed to the potential role of government and NGO support in promoting adoption (Table 2), the field findings indicate that such support is largely absent or insufficient. No significant initiatives were reported in Inharrime or Morrumbene, and only minimal NGO activity was noted in Jangamo (Table 5). This disconnection between recommended and actual institutional involvement highlights a gap between policy recommendations and implementation on the ground.

• Cultural and market factors

Cultural resistance to new technologies is mentioned in several literature sources (Table 1); however, field data did not strongly support this as a barrier in the Mozambican districts studied. Instead, other socio-economic realities, such as consumption fatigue during mango harvest season and a strong reliance on informal market systems like the “maguevas”, shape technology adoption dynamics (Table 4). These context-specific insights are not well captured in the broader literature and point to the importance of tailoring interventions to local social and market structures.

• Perceived benefits and drivers

In both the literature and interviews, the benefits of solar drying, such as reduced post-harvest losses, improved product quality, and potential for income generation, are acknowledged. However, field data show significant variation in perceptions of these benefits across districts. For instance, while 75% of respondents in Inharrime recognized multiple benefits of solar drying, only 3% did so in Morrumbene (Table 5). This suggests that perception gaps may influence willingness to adopt and could be addressed through targeted awareness campaigns.

• Market opportunities

While the literature identifies growing demand and market potential as key drivers (Table 2), the field findings suggest limited local market perspectives and weak integration into national or regional markets (Table 5). Most respondents saw only local sales opportunities, reflecting a narrower scope of market engagement. This mismatch points to the need for interventions that not only improve technology access but also enhance market connectivity and visibility for dried products.

Table 6 summarizes the most important factors discussed in the comparison between the literature and the field interview findings.

4. Discussion

While the potential of solar drying technologies to address post-harvest losses has been widely discussed in the literature, this study adds value by providing empirical, first-hand evidence from smallholder farmers across three under-researched districts in southern Mozambique- Inharrime, Jangamo, and Morrumbene. This contextual specificity allows for a deeper understanding of how financial capacity, gender roles, market integration, and institutional support vary locally and how these variations critically influence technology adoption potential.

Despite their low-cost and energy-efficient design, the widespread use of improved solar dryers is constrained by unaffordable upfront costs and insufficient farmer training and outreach [26,27]. High mango losses, often exceeding 50% in Jangamo and Morrumbene, underscore the urgent need for accessible preservation technologies, like improved solar dryers. These losses not only undermine the economic viability of mango farming but also pose serious risks to local food security. Improved solar dryers could provide an effective solution by enabling year-round preservation of mangoes, thereby reducing losses, enhancing product quality, and stabilizing market availability.

Traditional preservation methods severely restrict the year-round availability of mangoes, limiting their source of income. Solar drying technology offers a dual benefit: not only does it minimize the post-harvest losses, but it also increases the opportunity for income generation. Despite its clear benefits, the adoption of solar drying technology is hindered by various barriers. As confirmed in field interviews, cost is the most frequently cited barrier, echoing prior studies. Without tailored financial mechanisms, even interested farmers remain unable to adopt the technology. Additionally, policy gaps and broader economic constraints further complicate the landscape, as highlighted by [13]. Limited exposure to solar drying methods and scarce training opportunities further hinder technology uptake. This was reflected in the field data, where more than 80% of farmers reported having no prior knowledge of mango drying, and less than 5% had ever received any training, closely mirroring the knowledge-related barriers identified in the literature. This lack of understanding diminishes the perceived value and uptake of improved solar dryers, even in regions characterized by high mango production.

In remote areas, institutional support is often minimal, with NGOs and government agencies typically failing to offer the essential technical assistance [13,63]. The field interviews validated this gap, with no notable support structures identified in Inharrime and Morrumbene and only a limited NGO presence in Jangamo. To overcome these barriers, coordinated, multisectoral interventions are essential. Successful examples from other countries can provide a helpful framework. For instance, a project in Kenya, implemented by the African Centre for Technology Studies (ACTS), UNEP, and KIRDI, managed to deploy 500 low-cost improved solar dryers over five years, benefiting over 40,000 smallholder farmers. This initiative emphasized inclusive entrepreneurship and green job creation, particularly for women and youth (https://acts-net.org/acts-to-scale-up-solar-drying-to-reduce-post-harvest-losses, accessed on 24 April 2025).

Such partnerships between NGOs and governmental agencies could significantly enhance the uptake of solar drying technologies in Mozambique by supporting training initiatives, facilitating access to affordable technology, and strengthening market connections. This need for multi-actor engagement was not only emphasized in the literature but also indirectly reflected in the field results, where lack of coordination, weak market linkages, and insufficient input support were recurrent themes. Outreach campaigns that highlight the economic benefits of solar drying could motivate more farmers to adopt these technologies. Additionally, financial instruments such as microloans, grants, and subsidies are crucial to alleviating the initial investment burden. Public-private partnerships can further support the development of a robust value chain [13,63].

Agricultural extension officers will play a pivotal role in facilitating technology adoption. By connecting farmers to training, input, and market opportunities, they can significantly enhance the implementation of solar drying practices. However, current extension models are often limited in scope, as noted by [64], underscoring the necessity of a shift toward agripreneurship-focused advisory services that align more closely with modern post-harvest requirements.

The successful adoption of solar drying technologies offers numerous benefits, including reduced food losses, improved preservation of the nutritional content of mangoes, and enhancement of the overall quality and marketability of dried products. Smallholder farmers stand to gain from lower operational costs, long-term savings, and improved incomes [63,65]. However, interview results showed varying perceptions of these benefits, with respondents in Inharrime demonstrating higher awareness than those in Morrumbene, suggesting a need for localized awareness campaigns to address perception gaps.

Global examples validate these assertions. In countries such as Thailand, India, Kenya, and Uganda, the implementation of hybrid and conventional solar dryers has improved farmers’ access to higher-value markets while simultaneously reducing environmental impacts through decreased reliance on firewood [13,16]. Development agencies, governments, and cooperatives have supported this adoption through various strategies, including subsidies, shared infrastructure, and training initiatives, demonstrating an integrated approach that leads to improved food security and greater economic resilience. To replicate these successes in Mozambique, interventions must be grounded in both empirical evidence and community realities, as revealed through the triangulation of literature and field data presented in this study.

Women’s significant role in mango farming, particularly in Morrumbene, where they represent 59% of respondents, suggests that gender-responsive programming could enhance adoption. Similar gender-based approaches have proven effective in other regions where empowering women with solar drying technology led to broader household benefits and improved nutritional outcomes [63].

5. Conclusions

Mango production provides an ideal entry point for introducing solar drying due to its seasonality, high perishability, and widespread cultivation among smallholder farmers. Targeting mango production for solar drying interventions may serve as a catalyst for broader adoption of post-harvest technologies, offering a scalable entry point with both economic and nutritional benefits.

This study emphasizes the significant potential of solar drying technology to mitigate post-harvest losses of mangoes among smallholder farmers in Mozambique. While improved solar dryers offer advantages such as energy efficiency, environmental sustainability, and the enhancement of product quality, their broader adoption remains hindered by unaffordable setup costs, low farmer capacity, and limited institutional engagement.

The absence of institutional support remains a critical barrier, limiting farmers’ access to training, financing, and essential services. Despite these obstacles, smallholder farmers exhibit a willingness to adopt improved solar dryers under conditions of affordability, access to training, and integration into market systems. However, the lack of familiarity with the technology, limited investment capacity, and the absence of supportive programs remain substantial hindrances, reinforcing the need for targeted educational programs to raise awareness and build farmer capacity.

Additionally, the underdevelopment of the mango value chain and the focus on staple crops by extension services exacerbate these issues. This prioritization has led to missed opportunities for value addition in mango production, particularly given the high post-harvest losses, exceeding 50% in some districts, and the low commercial returns reported by farmers.

To promote the adoption of solar drying technologies, it is imperative to implement coordinated, multisectoral initiatives that include tailored financial mechanisms, such as microloans and subsidies, and the incorporation of solar drying into agricultural extension agendas. Strengthening farmer cooperatives and fostering partnerships among public institutions, NGOs, and private sector actors are also critical to creating an enabling environment for scaling up these technologies. Moreover, interventions must be tailored to district-level realities, as disparities in willingness to invest, perceived benefits, and economic conditions were found to influence adoption potential.

To move from these insights to concrete action, the following policy recommendations are proposed:

• Subsidized Financing and Credit Schemes: Provide low-interest loans, microcredit options, or direct subsidies to reduce the high initial investment barrier for smallholder farmers.
• Targeted Training and Extension Services: Develop community-based training programs focusing on solar drying techniques, with a special emphasis on including women and youth.
• Local Manufacture and Maintenance Partnerships: Foster public–private partnerships to encourage local production and repair services for improved solar dryers, which can lower costs and improve sustainability.
• Demonstration and Outreach Programmes: Establish pilot units and information campaigns to showcase the benefits and proper use of solar drying technologies.
• Institutional Coordination: Integrate solar drying initiatives within broader national agricultural and post-harvest policies by fostering cross-sector collaboration among government departments, NGOs, and industry stakeholders.

By implementing these targeted measures, Mozambique can not only mitigate post-harvest losses in mango production but also enhance food security and improve rural livelihoods. Future research should assess the long-term impacts of such interventions to further refine adoption strategies. Furthermore, linking solar drying to nutritional benefits, such as reducing vitamin A deficiency, represents a promising avenue to strengthen both adoption and public health outcomes. Increased availability of dried mango could contribute to improved vitamin A intake among children [66,67], a public health priority in Mozambique [68,69,70].

One limitation of this study is its reliance on convenience sampling, which affects the representativeness of the findings. Since convenience sampling was used rather than random sampling, the perspectives gathered may not fully represent the broader population of smallholder mango farmers in Mozambique. Therefore, caution should be exercised when generalizing the findings to districts beyond those studied. Future research that employs probabilistic sampling techniques would be valuable in enhancing external validity.