#
Optimal Integration of Renewable Sources and Latent Heat Storages for Nearly Zero-Energy Buildings^{ †}

^{*}

^{†}

## Abstract

**:**

## 1. Introduction

## 2. Case Study and Methods

#### 2.1. The Project

#### 2.2. Case Study

^{2}.

^{2}(with 78 modules with a nominal power of 310 W each). The overall nominal power of the plant is 24.2 kW.

#### 2.3. Methodology

#### 2.3.1. Optimal Operations

_{e_in}), the electricity sold (c

_{e_out}), the gas purchased (c

_{g_in}) and the investment cost (c

_{inv}) are all expressed in EUR/day. These terms are obtained by multiplying the electricity (or the gas) cost times the energy absorbed by the system in the entire time evolution considered.

#### 2.3.2. Combined Design and Operation Optimization

_{e_in}), the electricity sold (c

_{e_out}), the gas purchased (c

_{g_in}) and the investment cost (c

_{inv}) are all expressed in EUR/day, as for the optimization described in Section 2.3.1.

## 3. Results

#### 3.1. Operations Optimization

#### 3.2. Combined Design and Operation Optimization

## 4. Comparison and Discussion

- Benchmark Case;
- Operation Optimization Case 1 (with thermal storage);
- Operation Optimization Case 2 (with electric storage);
- Combined Design and Operation Optimization Case 1 (with thermal storage);
- Combined Design and Operation Optimization Case 2 (with electric storage) and a detail of the fraction covered by investment and operations.

## 5. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 1.**RE-COGNITION project’s main concepts [16]: (

**a**) development of new renewable small-scale technologies; (

**b**) development of platform for the optimal integration of renewable technologies in building context.

**Figure 2.**Schematic of the system considered and renewable energy sources (RES) technologies in the present work.

**Figure 3.**Daily evolution of the dwelling consumptions for a typical cold winter day: (

**a**) electricity consumption; (

**b**) thermal consumption.

**Figure 5.**Daily consumption and production pattern for Case 1: (

**a**) thermal consumption; (

**b**) electricity consumption.

**Figure 7.**Daily consumption and production pattern for Case 2: (

**a**) thermal consumption; (

**b**) electricity consumption.

**Figure 8.**Daily consumption and production pattern in case of investment cost inclusion for Case 1: (

**a**) thermal consumption; (

**b**) electricity consumption.

**Figure 9.**Daily consumption and production pattern in case of investment cost inclusion for Case 2: (

**a**) thermal consumption; (

**b**) electricity consumption.

**Figure 10.**Daily cost for operations and investment for the Operational Optimization (for both Case 1 and Case 2) and Combined Design and Operation Optimization (for both Case 1 and Case 2).

Case N° | Technology 1 | Technology 2 | Technology 3 | Technology 4 | Technology 5 | Technology 6 |
---|---|---|---|---|---|---|

1 | Small-scale wind turbine | Photovoltaics | mCHP | Gas heat-only boiler | Air heat pump | Latent heat storage |

2 | Small-scale wind turbine | Photovoltaics | mCHP | Gas heat-only boiler | Air heat pump | Electric storage |

Technology | Details | Cost and Ref. | Lifetime and Ref. | ||
---|---|---|---|---|---|

Photovoltaics | - | 2280 (EUR/kW) | [17] | 20 | [17] |

Wind Turbine | Small scale | 6424 (EUR/kW) | [18] | 25 | [22] |

mCHP | Biogas microturbine | 1950 (EUR/kW) | [19] | 10 | [23] |

Heat pump | Traditional air heat pump | 720 (EUR/kW) | [17] | 15 | [17] |

Gas heat-only boiler | Condensing boiler | 180 (EUR/kW) | [17] | 12 | [17] |

Latent heat storage | Paraffin wax PCM | 50 (EUR/kWh) | [20] | 30 | [20] |

Electric storage | Li-ion | 546 (EUR/kWh) | [21] | 10 | [21] |

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**MDPI and ACS Style**

Guelpa, E.; Mancò, G.; Verda, V.
Optimal Integration of Renewable Sources and Latent Heat Storages for Nearly Zero-Energy Buildings. *Proceedings* **2020**, *58*, 35.
https://doi.org/10.3390/WEF-06914

**AMA Style**

Guelpa E, Mancò G, Verda V.
Optimal Integration of Renewable Sources and Latent Heat Storages for Nearly Zero-Energy Buildings. *Proceedings*. 2020; 58(1):35.
https://doi.org/10.3390/WEF-06914

**Chicago/Turabian Style**

Guelpa, Elisa, Giulia Mancò, and Vittorio Verda.
2020. "Optimal Integration of Renewable Sources and Latent Heat Storages for Nearly Zero-Energy Buildings" *Proceedings* 58, no. 1: 35.
https://doi.org/10.3390/WEF-06914