New Software for the Techno–Economic Analysis of Small Hydro Power Plants
Abstract
:1. Introduction
- Climate change represents the most pressing existential threat to humanity;
- An era of low-carbon energy, characterized by dramatic changes in the energy supply–demand relationship;
- About 770 million people still do not have access to clean, affordable, and reliable electricity, and almost one in three people do not have access to safely managed drinking water;
- The Paris Agreement also includes the transition from fossil to renewable energy sources;
- As a renewable energy, hydropower plays an essential role in decarbonization of the energy system (especially small hydro power plants (SHP)) and play an important role for the global energy supply;
- Driven by the increasing demand for energy and global climate change, many countries have given priority to hydropower development in the expansion of their energy sectors.
- A mature technology which can easily be designed, operated, and maintained locally;
- Economically feasible and has minimal impact on the environment;
- Contributes greatly to solving the problem of rural electrification, improving living standards and production conditions, promoting rural economic development, alleviating poverty, as well as reducing emissions;
- Favoured by the international community, especially by developing countries;
- Has the lowest electricity generation prices of all offgrid technologies, and the flexibility to be adapted to various geographical and infrastructural circumstances.
2. Existing Software for the Analysis of SHP
2.1. Conventional Software Tools for SHP Assessment
2.1.1. SMART Mini-Hydro
2.1.2. RETScreen International Clean Energy Project Analysis Software
2.1.3. Small Hydropower Plant Software—NTNU
2.1.4. HydroHELP Design Cost Tool
- HydroHELP 1.4 for turbine selection;
- HydroHELP 2.4 for Francis turbines;
- HydroHELP 3.4 for impulse turbines;
- HydroHELP 4.4 for Kaplan turbines.
2.1.5. Integrated Method for Power Analysis (IMP 5.0)
- models for flood frequency analysis;
- models for the analysis of the flow duration curve (FDC) and hourly and daily flow values based on data on precipitation, temperatures, and the description on the left;
- a simulation model for estimating electricity production from the collected data on a daily or annual level;
- fish habitat analysis module.
2.1.6. PEACH Software
2.1.7. The Hydropower Evaluation Software (HES)
2.2. GIS Applications for Evaluating Hydropower Potential
2.2.1. NVE Atlas
2.2.2. The Rapid Hydropower Assessment Model (RHAM)
2.2.3. The Virtual Hydropower Prospector (VHP)
2.2.4. Hydrobot
2.2.5. VAPIDRO ASTE
3. New Software (Tool) for Techno-Economic Analysis of SHP
3.1. Software Structure
3.2. Net/Designed Flow Module
- According to the desired share in the calculated average flow.
- Direct user input of the desired value.
- Direct manual input of the designed flow value.
- Calculation of the value of the designed flow according to the duration in the flow duration curve.
3.3. Net Head Module
3.4. Turbine Module
3.5. Turbine Selection Module
3.6. Energy Production Module
- Generator efficiency;
- Transformer efficiency;
- Transmission efficiency.
3.7. Investment Module
- Dam construction costs;
- Costs of construction of the catchment structure;
- Construction costs of the power plant building;
- Turbine, generator and transformer costs;
- Costs of supply and drainage structures;
- Costs of other mechanical and electrical equipment;
- Cost of work, services, and design.
3.8. Financial and Economic Module
3.9. Sensitivity Module
4. Software Verification
4.1. SHP Korana 1
4.2. Input Data
4.3. Results
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Appendix A. Flow Duration Curve
Appendix B. Flow of the Ecological Minimum
Appendix B.1. Methods Based on Hydrological or Statistical Values
Method | Equation | Description |
---|---|---|
Method 10% of average flow value | (A3) | The flow of the ecological minimum must be greater than 10% of the average value of the flow QAV. Attention should be paid to the fact that there is a temporal change in the flow of the ecological minimum QECO. In order to meet the stated conditions, it is necessary to continuously measure the flow at different sections of the water flow, which makes this method demanding. |
Lanser’s method | (A4a) (A4b) | The calculation of the flow of the ecological minimum is set in a certain interval, more precisely between 5 and 10% of the mean value of the flow QAV. |
Jager’s method | (A5) | It suggests considering the importance of the fish population in the watercourse; the flow of the ecological minimum is calculated as 15% of the mean value of the flow QAV. |
The Montana method | (A6a) (A6b) | It takes into account the economic importance of fishing in a certain watercourse. In case of a high economic importance of fishing, QECO is calculated for an interval 40–60% of the average flow QAV, while in case of a small economic importance of fishing, QECO is calculated as 10% of the QAV. |
Steinbach’s method | (A7) | QECO is calculated in such a way that it must be equal to the minimum average flow QAV,min, taking into account a longer period of time and the seasonal distribution, i.e., the division into summer and winter periods. |
Rheinland-Pfalz method | (A8a) (A8b) | Calculation of QECO is set in a certain interval, more precisely between 20 and 50% of the minimum average flow value QAV,min. |
Alarm limit value method | (A9) | It imposes the calculation of QECO as the flow needed to ensure the ecological requirements of the watercourse in the amount of 20% of the flow that occurs at least 300 days a year Q300. |
Sawall and Simon method | (A10a) (A10b) | QECO is calculated in the interval of 7–100% of the minimum average flow in the month of August , taking into account the longer time period of flow measurement. |
The method of fitting with the flow duration curve (Fitting to FDC) | (A11) | It prescribes QECO in such a way that the amount of flow QECO is calculated as the mean value of the difference of the flow between dry and rainy years which is present for more than 84% of the duration of one year. The differences between the flow duration curves for dry and rainy years are particularly pronounced in some geographical areas; therefore, it is possible to observe significant differences in flow values Q84%. Q84%,S represents the value of the flow that is present for 84% of the duration of the dry year, and Q84%,K represents the value of the flow that is present for 84% of the duration of the rainy year. |
Appendix B.2. Comparative Analysis of Methods Based on Hydrological Values
Appendix B.3. Methods Based on Water Depth and Velocity
Method | Equation | Description |
---|---|---|
Steiermark method | (A12a) (A12b) | The flow rate and water depth are measured in the area between the partition and the drainage system. The set conditions determine that:
|
Oregon method | (A13a) (A13b) | The requirements of the Oregon method differ significantly from the Steiermark method, with measurements being made on the depleted portion of the watercourse. Relevant conditions are also related to the inlet velocity of the current within the limits of 1.2–2.4 m/s, and the water depth within the limits of 0.12–0.24 m. vMIN and vMAX are the minimum and maximum inlet velocity, and are the minimum and maximum water depth in the exhausted part of the water flow, and bUSE is the useful water depth |
Oberösterreich method | (A14) | It imposes a condition only on the water depth in the exhausted part of the water course, which is 0.2 m. |
Appendix C. Net Flow Calculation
Calculation of the Flow of a SHP
- By direct calculation from the given data in the flow curve;
- By manually entering the desired value of the designed flow.
Appendix D. Net Head Calculation
Appendix D.1. Flow Losses in Pipelines
Type of Loss | Equation | Description |
---|---|---|
Line losses | (A17) | is the total length of the pipeline, is the designed flow, Strickler’s roughness, and is the selected diameter of the pipeline calculated according to the designed flow and the given speed of water flow in the pipeline. |
Local losses | (A18) | is the corrected speed of water flow in the pipeline calculated as a function of the selected diameter of the pipeline , α is the size factor of local losses, and g is the acceleration of the gravitational force. |
The total losses | (A19) | It subtracts from the total realizable geodetic head. |
Appendix D.2. Flow Losses in Open Channels
Type of Loss | Equation | Description |
---|---|---|
Chézy-Manning equation | (A20) | A is the cross-sectional area of the channel, S0 is the slope of the channel, n is the Guckler–Manning coefficient, and Rh is the hydraulic radius of the channel. Rh is a measure of the flow efficiency in the channel depending on the cross-section of the channel. |
The hydraulic radius | (A21) | PL is the “wetted perimeter” of the channel under consideration. It is necessary to achieve the largest possible hydraulic radius of the channel in order to achieve greater efficiency. PL is the sum of the length of the submerged parts of the individual sides of the channel. |
Line losses in channels with an open water face | , (A22) with y1 = y2 = const. and v1 = v2 = const.: ; ; (A23) (A24) (A25) (A26) (A27) | S0 is the slope of the channel, LCHA is the length of the channel, and hL is the flow loss in the channel, n—the Gauckler–Manning coefficient. For a square cross-section: vCHA is the designed velocity of flow in the channel, hK is the height of the lateral sides of the channel, and wK is the length of the lower side of the channel. For a circular cross-section: DCHA is the diameter of the channel calculated according to the designed flow and the designed velocity in the channel. For a trapezoidal cross-section: is the angle between the side of the trapezoid and the lower base of the trapezoid . |
Appendix E. Calculation of SHP Parameters
Appendix F. Investment Calculation
Component | Equation | Description | |
---|---|---|---|
Dam | (A33a) | Coefficients a0–a3 are defined in accordance with the associated data and differ for each of the specified flow intervals. Higher order equations are applied for other flows. | |
(A33b) | |||
(A33c) | |||
Catchment structure | (A34) | The coefficients a1 and a0 differ for different flows and depend on the application of a particular type of intake, and ACS is the area of the intake determined on the basis of the given flow rate and flow speed in the intake. | |
The power plant building | (A35) | The coefficients a1 and a0 are different for different flows. | |
Turbinetype | Pelton | , ; (A36a) , (A36b) | The classification of coefficients a0–a2 is according to the calculated geodetic head. |
Francis | , ; (A37a) , (A37b) | The classification of coefficients a0–a1 is according to the calculated geodetic head. | |
Kaplan | (A38) | The classification of coefficients a0–a1 is according to the calculated geodetic head. | |
Cross flow, DIVE, Turgo, VLH | (A39) | The coefficients a0–a2 change depending on the number of installed turbines, P is the installed power of the turbine, and H is the calculated geodetic head. | |
Electric generator | (A40) | The price of the electric generator is expressed as a function of the installed power of the turbine. The coefficients a0–a1 are the same for all cases; however, with a turbine power of less than 500 kW, it is taken into account that the cost of the generator is included in the cost of the turbine, and it is omitted from the cost of the generator. | |
Transformer | (A41) | The coefficients a0–a1 depend on the installed power of the turbine and are divided into three classes. | |
Pipelines | (A42) | The coefficients a0–a2 depend on the installed power of the turbine. | |
Canals | (A43) | ||
Other mechanical and electrical equipment | (A44) | The coefficients a0–a1 depend on the number of installed turbines. The final price depends on the number of turbines installed, as well as on the power of the turbines and the calculated geodetic head. | |
Cost of work | (A45) | ||
Cost of services and design |
Appendix G. Calculation of Economic and Financial Parameters
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Software Tools | Features | ||||||
---|---|---|---|---|---|---|---|
Name | Developer | Applicable Countries | Hydrology | Power and Energy | Coasting | Economic Evaluation | Preliminary Design |
Integrated method for power analysis (IMP) | National Resources Canada and POWEL | International | Model | + | - | - | - |
RetScreen® | National Resources Canada | International | FDC | + | + | + | - |
PEACH | ISL Bureau d’Ingenieurs Conseils, Paris, France | International | FDC | + | + | + | + |
Hydropower Evaluation Software (HES) | Department of Energy, Idaho Engineering and Environmental Laboratory, USA | USA | MAF | - | - | - | - |
SMART Mini-Hydro | ERSE SpA, Milan, Italy | Italy | FDC | + | + | + | - |
Hydrohelp | Gordon J.L and OEL-HydroSys, Canada | International | FDC | + | + | + | - |
SHP Atlas on the Internet | Features | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
Name | Developer | Applicable Countries | Accessibility | Hydrology | Power and Energy | Possible SHP Sites | Economic Evaluation | Proximity Information | SHP Renovation | Accounting for Other Water Uses, Minimum Flow Releases |
NVE Atlas. Potential for SHP plants | Norwegian Water Resources and Energy Directorate (NVE), Trondheim | Norway | Open access, interactive web-based maps | MAF | + | + | + | + | - | - |
Virtual Hydropower Prospector (VHP) | Idaho National Laboratory, Idaho | USA | Open access, interactive web-based maps | MAF | + | + | + | + | + | - |
RHAM | Kerr Wood Leidal Associates Ltd. (KWL) | British Columbia, Canada | Open access, interactive web-based maps | MAF, FDC | + | + | + | + | - | + |
Hydrobot | Nick Forrest Associates Ltd. et al. | Scotland | Limited access | FDC | + | + | + | + | - | + |
VAPIDRO ASTE | ERSE SpA, Milan | Italy | Open access, interactive web-based maps | MAF | + | + | + | + | - | + |
Parameter | From [22] | New Software | Difference [%] |
---|---|---|---|
Selected turbine | VLH | VLH | - |
Maximum turbine power [kW] | 380 | 383 | 0.7% |
Nominal power [kW] | 368 | 344 | −6.5% |
Average power [kW] | 377 | 312 | −17.2% |
Electricity produced [MWh] | 2768 | 2298 | −16.9% |
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Guzović, Z.; Barbarić, M.; Bačelić Medić, Z.; Degiuli, N. New Software for the Techno–Economic Analysis of Small Hydro Power Plants. Water 2023, 15, 1651. https://doi.org/10.3390/w15091651
Guzović Z, Barbarić M, Bačelić Medić Z, Degiuli N. New Software for the Techno–Economic Analysis of Small Hydro Power Plants. Water. 2023; 15(9):1651. https://doi.org/10.3390/w15091651
Chicago/Turabian StyleGuzović, Zvonimir, Marina Barbarić, Zlatko Bačelić Medić, and Nastia Degiuli. 2023. "New Software for the Techno–Economic Analysis of Small Hydro Power Plants" Water 15, no. 9: 1651. https://doi.org/10.3390/w15091651
APA StyleGuzović, Z., Barbarić, M., Bačelić Medić, Z., & Degiuli, N. (2023). New Software for the Techno–Economic Analysis of Small Hydro Power Plants. Water, 15(9), 1651. https://doi.org/10.3390/w15091651