Our second-biggest source of carbon emissions is energy [1], and the recent jumps in energy prices and blackout preparations have only highlighted its importance. Being renewable, reliable and requiring minimal operational costs, solar PV is a viable and competitive solution to energy provision. The EU’s solar rooftops initiative requires all commercial and public building rooftops to have solar installed by 2027, and new residential buildings to include rooftop solar from 2029 [2], while in the UK, the government previously envisioned the 250,000 hectares of south facing, mid-size, commercial and industrial roofs would play a major role in our future energy mix[3], and more recently, our energy security strategy expects a fivefold-increase in solar PV by 2035 [4].
Benefits of Solar PV
Installing Solar PV generates a multitude of benefits, which can be broadly categorised in economic, environmental and commercial.
Economic Benefits: With rising energy costs and a dramatic cost reduction of 85% in the past decade, it has never been more cost-effective to invest in onsite solar PV generation. Not only would this lower your energy bills, but it also supports your electricity supply stability and independence when coupled with battery storage, supporting greater energy self-sufficiency, individually and nationally.
Environmental Benefits: Working in harmony with natural processes, solar PV helps reduce CO2 emissions and contributes to limiting global warming to 1.5°C.
Commercial Benefits: With customers, employees and investors increasingly scrutinising businesses’ environmental and social practices, a solar PV system would reduce your emissions, foster warming relations with your local community through stimulating installation and maintenance jobs, support your company’s sustainability strategy and generate a positive public profile. Moreover, a solar PV system increases your property’s value, and to maximise cost-effectiveness, try working collectively with your neighbours and other building owners to quote a larger solar PV system, which could yield cheaper per unit installation costs.
A Quick Introduction to Solar PV
Solar PV, or Solar Photovoltaics, are panels that utilise some clever chemistry to convert light into electricity. DC (Direct current) current is produced by the panels, which is then converted to AC (Alternating current) by an inverter, before being used by appliances, stored in batteries (if one is installed), or exported to the grid. The key variables that affect the amount of electricity produced depend on the following factors:
Light intensity: the brighter the light source, the more electricity generated. However solar PV can still generate electricity on cloudy days (just not as much).
Panel efficiency: the higher the panel rating, the more electricity generated. Your installer will be able to advise on this.
Shading: shadows, snow, dust and grit all block out (some) light, resulting in less generation.
Roof orientation: the ideal orientation is due South, or 180°. Anything that deviates from this will generate less electricity, although a roof orientation from due East (90°) to due West (270°) is considered financially viable, while any North-facing (0-90°, 270-360°) roof is not.
Panel angle: the optimal angle for solar PV panels in Coventry is 36°, however this is not always practical or space-efficient. Your installer will advise you on the optimal balance between required system size, panel angle and rooftop space utilisation.
And remember, the brighter/ more intense the light, the more power that is generated, so your solar PV system would generate the most power around midday, significantly more during summer than winter, and none at all at night.
[2]: https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=COM%3A2022%3A221%3AFIN&qid=1653034500503