We started in Solar Thermal and the delay in the RHI which was supposed to be introduced in April 2011 forced us to add another add another technology: PV. We got our acceditation two weeks before the announcement of the the cuts to FITs in October last year. Our timing could not have been better!
Currently Solar thermal is asleep. To put some perspective on this under phase one of the Renewable Heat Premium Payment Scheme 1772 vouchers were redeemed for solar thermal. There are 1298 MCS registered solar thermal installers. Over the 12 month period of the scheme this means they installed an average of 1.36 systems each!! The total figure of installations will be higher as this does not take into consideration new build. The problem with the RHPP is that although it has been stated that all ST systems installed since July 2010 will qualify for the RHI, no one knows what this means. The current incentive is "I'll give you £300.00 now but I am not going to tell you what You will get for the 20 years of the RHI." Little wonder the scheme has been a disaster.
Solar thermal should be a sleeping giant. It is a far more appropriate technology for a lot of properties than PV. Area of roof covered is only 3 to 4 sq Metres. You can install good quality kit anywhere from east to west and compensate through sizing. Shade is not such a critical issue.
The down side is the proliferation of Combi boilers which make installation more problematic, especially in the area of legionella prevention. There are way too many properties where people have been sold the option of a combi, where quite frankly it was not the best solution for them.
The domestic side of the RHI looks promising. We are likely to see the 20 year qualification period compressed down to something like 7 years. It is hoped there may be full capital recovery in this period. Payments will be deemed, not measured. The caveat to this is it is not yet clear what the control mechanism will be to stop the scheme running away as the FIT did. We could end up with a stop go situation where it is rationed. It is hoped solar thermal will be treated differently to the other renewable heat technologies. The latter may only qualify in off-grid areas. ST is appropriate for any property, on or off grid. It is also hoped that there will not be a nutty digression mechanism. ST is a mature technology, and is unlikely to benefit from the kind of cost reductions seen in PV. Much of it also contains a lot of copper or stainless steel, neither of which is getting cheaper.
There should be a consultation document on the domestic RHI this autumn which will give a better picture of DECC's thinking on the issue.
If I were a PV installer looking at ST, I would approach it the same way I approached PV. I hold qualification in PV, but am not an electrician. The electrician I have worked with for years does all that. I design and specify. I also have a background in building renovation that makes building regs and roofs much easier. Do bear in mind the recent consultation on alignment of MCS with National Occupational Standards. I went through the experienced worker route over plumbing before we started in ST having my work based skills assessed as exceeding NVQ/SVQ 2, meaning good for everything except gas. ( I work with a GAS SAFE heating engineer for that). For ST you need a specific ST qualification such as the BPEC course, and unvented cylinder as a minimum. Things like water bye-laws and energy conservation are also useful. The BPEC course is not beyond someone with a working knowledge of plumbing and the kind of practical skills electrical engineering brings. My advice would be use a plumber and ensure they hold a ST qualification. You can't do everything yourself.
System design and implementation can be complex due to the varied and different ways water temperature is topped up when there is insufficient solar gain. In a lot of properties you will be dealing with the history of plumbing. Do not be fooled in to thinking it is an easy option to do well.
I retain my optimism for solar thermal. It is a great technology. You store everything you produce and use it as you need it. Do not enter unless you have the same kind of belief in it that I do.
