Small Scale Photovoltaic Installations - Use of RETScreen Software

January 09 Photovoltaic Project Analysis Using RETScreen software Case study : 36 kWp installed in South of Spain, grid connected, fix structure Fernando Nuño European Copper Institute [email_address] In cooperation with Infrysol http://www.infrysol.com / http://www.retscreen.net/

Index

What a PV system consists on?

Fix Structure vs Tracking System

RETScreen Analysis

Required inputs

Computing

Results

What a PV system consists on? Photovoltaic cells connected into modules Modules grouped into panels, panels grouped into arrays Power conditioning unit (inverter) Pictures: Fernando Nuño Transformer Grid Connection

Fix Structure vs Tracking System Pictures: Fernando Nuño No moving parts, lower maintenance, more reliable operation Needs higher maintenance and suffers higher risk of unscheduled outages Easy to install and operate Needs more solid foundations and stiff structure : +1€/Wp Average production in South of Spain : 1500 kWh/kWp Average production in South of Spain : 2000 kWh/kWp (+30%)

Analysis with RETScreen – Required inputs Selected PV panels

Technical characteristics

Nominal Power under Standard conditions

Selected Inverters Transformer Land

Owned : how much it cost?

Renting: annual fee?

Operation

Recurrent costs: monitoring and security, tracker maintenance, land renting, insurances

Efficiency in operation

Efficiency in operation

Miscellaneous

Cabling, civil works, grid connection works, support structure / trackers

Investment Investment Investment Investment Investment Annual expenditure

Analysis with RETScreen – Required inputs Selected PV panels 1.94 m 2 280 Wp Picture: Suntech Efficiency = 280 W / [1,94 m2 * 1000 W/m2] = 14.4%

Analysis with RETScreen – Required inputs Selected inverters 3.5 kW 95% eff Picture: Fronius

Analysis with RETScreen – Required inputs Site characteristics

Location

Here Here

Analysis with RETScreen – Required inputs Site characteristics

Building orientation related to North/South and roof slope

South Picture : ε α β

Analysis with RETScreen – Computing Two types of analysis : first approach or developed in depth Project Information Grid connected or off-grid applications

Analysis with RETScreen – Computing Site reference conditions Large choice of locations around the world Provides irradiation, temperature and wind data per month

Analysis with RETScreen – Computing Type of PV system Two types of analysis : 1) first approach or 2) developed in depth Fixed, 1 axis track, 2 axis track

Analysis with RETScreen – Computing Computing slope and azimut South Picture : ε α β

Slope = arctan [tan 2 ( α ) + tan 2 ( β )] 0,5

Azimut = ε + arctan [ tan( α ) / tan( β )]

Analysis with RETScreen – Results Exported Electricity Feed-in tariff applicable in Spain up to Sept 2008 Estimated Electricity Export to grid

Analysis with RETScreen – Results Actual vs Estimated Export -2% May was particularly cloudy and rainy

Analysis with RETScreen – Results Number of panels Introduce the power to install and the panel efficiency Obtain the number of panels and the solar collector area

Cost breakdown 4,5 €/W 6,1 €/W

Cost breakdown

Analysis with RETScreen – Results Financial analysis Output: Cumulative Cash Flow Inputs Outupts

Analysis with RETScreen – Results CO2 emission analysis Reference power generation technology Obtain Net annual emission reduction

Analysis with RETScreen – Two axis track Two axis track 33.6 kW

Thank you! http://www.infrysol.com/ http://www.retscreen.net/ SOFTWARE CASE STUDIES by:

Anex – Slope and Azimut calculations South Picture : ε α β Find γ such that δγ / δε = 0 (maximum slope) α β ε η = 90º - ε

Anex – Slope and Azimut calculations

Anex – Slope and Azimut calculations Find γ such that δγ / δε = 0 (maximum slope)

Anex – Slope and Azimut calculations

Annex – Available surface on roof Where α is the lowest sun height (21 december in North hemisphere) Where β is the slope