Solar challenges in 2017 In it for the long term James Page Head of Engineering

When does solar need subsidy ? - in the absence of carbon taxation (or rationing) - long term (40 year?) investment – society values future income more than individuals or companies

Step changes in FITS

Some back of envelope numbers: Cost of system: typically £900-£1100 / kW 1kW will generate 850-1000 kWh / year So ~ £1 / kWh for many years (degradation say 0.5% / year ) 1 kWh brings 4p of FIT + 12p saving or ~7p PPA or 5p export

Rates of Return (50kW, London) Installed Price % electricity used on site Can reach rates of return >15% Should leave space for: Returns to shareholders Community Benefit Attractive PPA price to host May imply new types of communities …. 23/2/2017

Still a good investment even with lower FITs Real 20-50kW systems

Return on investment: - location (& shading) - system kWh/kW (& pitch etc) - FIT rate (EPC/date/multiple) - usage on site - reliability

Microgrids Financial benefits require selling kWh to users – either on or off site. Export prices difficult to predict – low at the moment but move towards ‘time of use tariff’ with Smart metering roll out 2/23/2017

Return on investment – 20kW example New FIT rates (4.59p) bring IRR from 16 to 12%, assuming 80% usage on site (and ‘deemed’ export.) 2/23/2017

Conclusion: Replace individual meters with ‘private metering’ to increase % used on site. Ideally meters would be located in one place, to ease cabling 2/23/2017

Limited roof space? East/West = more kWh

Science Museum , South Kensington

Shading analysis – Senate House, London

Comparing with actual weather data:

Measuring on site use

Measuring system performance: Bungay, 50kW

Do panels need cleaning ? Relative performance before and after :

How often? Performance change 1 and 2 weeks after cleaning ?

Thank you “It is no longer a question of whether or not renewables can take the lion’s share of global power generation, but how long it will take to get there.” Eco-business 22.1.15 James Page 0207 697 1000 james@joju.co.uk