Following the completion of a recent project I visited our customer to present the handover file for a 34.5kWp photovoltaic (PV) installation designed to produce around 31 megawatt hours of electricity a year. As the site in question is a Benedictine abbey providing a home for a community of monks as well as a venue for concerts, conferences, study and of course worship I thought a few words might be of interest and demonstrate the value of persistence on the part of both customer and supplier. Here are the essentials: Planning The grounds of the abbey contain several listed buildings, so planning permission was needed for this installation. The basic requirement turned out to be that the whole installation would need to be invisible from the ground; a bit of design tweaking and an acceptance that not every available surface needed to be filled with modules dealt with this. Energy Performance Certificate (EPC) We encountered the bizarre workings of the Feed in Tariff system and the requirements for energy efficiency. Background
When the Government was looking for ways to bring the costs under control a couple of years ago it introduced a condition that installations attached to buildings with poor energy performance ratings would receive a much reduced level of subsidy. Superficially this seems fair, as was the use of the Energy Performance Certificate (EPC) system as the measure of that performance.
You now need to produce an EPC showing class D or better before you can collect the subsidy; still logical in a world where all subsidies are going to homeowners. Now the Government and their advisors are surprised that the take up by the controllers of commercial rooftops is very low; which is bad because the greatest environmental (as opposed to electoral) benefit is achieved when rooftop PV systems supply the occupier of the building with energy to match the use within the building. Transferring electricity to the grid starts to create losses and that is largely what is happening on a sunny day in June when most households do not use much in the way of lighting, heating or heavily consumptive appliances.
Most commercial buildings have a fairly high and continuous use of electricity throughout the year and any element of air-conditioning is likely to increase demand further in the summer months, when PV is at its zenith. The calculations required for EPC rating do not take into account the equipment in use within the building, just the "climate control" aspects of heating, cooling and insulation, plus lighting. Summary
The subsidy system gives most to those who have the best heating and insulation, even though they have virtually zero effect when the solar energy production is most efficient. Relatively therefore it penalises industrial property the most, which is the biggest user of on-site electricity relative to available roof space.
The good news is that buildings that do not have heating systems are exempt from the EPC requirement. They should be able to collect the higher subsidy rate to encourage them to try to overcome the costs of retrofitting PV modules on large rooftops which were not originally designed for such installations.
The snag is that most unheated industrial buildings are simply there for storage and use very little power. The sting in the tail
Good news again. There are a number of other classes of property that do not require EPCs, including (yes I am getting back to the subject) Places of Worship!
Guess what; it's not such good news as these other exemptions are not recognised by the Feed in Tariff rules, so unless you can produce an EPC of D or better you are stuck with the same tariff as a 5,000 kWp solar farm.
Even if you had a well-insulated church you still couldn't collect because EPC assessors will not assess a property which is exempt from requirements. So don't expect to see many more churches use their large south facing rooftops to supply the place of worship or the attached nursery, community hall etc. Sting avoided The trustees of the abbey are used to long term planning though and are not frightened of a bit of technology, so when a new library was added a few years ago low carbon was up there with shelving on the wish list. They used ground source heat pumps to extract not only heat from 80m bore holes but also an EPC rating of C..... Bazinga! A good outcome for all We were in business. The arcane rules, based on residential property, decree that one building on the site needs an EPC. We were able to overcome the obstacles (which could have been designed to collect votes and save money rather than achieve a low carbon economy) to install a system which will provide all the power requirements of the abbey and ancillary buildings for brief periods during the summer and overall significantly reduce both costs and carbon footprint. Even this wouldn't have been possible however had the trustees not been prepared to take a long view and see the investment for what it is, a way of fixing a substantial proportion of electricity costs for at least 25 years with a massive saving in carbon emissions, even after allowing for manufacture and installation. In case you are worried, not a single module can be seen from ground level; so no blot on the architectural qualities of this beautiful and tranquil haven. The moral(s)
Long term thinking wins over a poorly designed incentive scheme.
These benefits could be available to British industry too.
The Government is now of the view that commercial property as a basis for micro generation needs to be exploited and accept that rule changes need to be considered.
Experience has shown that being prepared and ready to take advantages of new initiatives gets the best results.
If a location and use is fundamentally suitable for solar power generation (we can tell you pretty quickly if it is not) then persistence and a creative supply partner can deliver.