Getting Quotes

I think that everybody knows that, before embarking on any major home-improvement project, it is advisable to get multiple quotes. What people DON'T tell you is what a difficult process this is. Apart from the rigmarole of arranging for people to come and look at the property to quote, with SolarPV systems there are a lot of possibilities to be considered.

Just a few of these are:

  • How many panels?
  • Which roofs to fit them on?
  • How big a capacity should the inverter have?
  • Should batteries be fitted? If so, what capacity?
  • Will nesting birds be an issue?
  • Is it best to have the latest, highest-capacity panels?
  • Will the system provide power during a mains outage?

We started out knowing very little about SolarPV systems. I am an experienced electronics and software engineer, but my knowledge of SolarPV technology was virtually zero.

Our initial benchmark for cost was the Costco Website. This gave us an approximate costing for several different sizes of systems and battery combinations

Next we had three companies come out to see the property and quote for a number of possible options. We tried not to "lead" them too much and let them recommend what they thought would be right for our property. Including the Costco systems this gave us a spreadsheet with seventeen different systems on it. Prices varied from a little over £9,000 to over £26,000. The least expensive system was solar only (without batteries) anf the most expensive had more panels and very large batteries.

Red Flags

There are a couple of things that should lead you to be immediately suspicious of any sales person:

  • If you are told "We can't fit Bird Guarding because it would invalidate the warranty" then you are either dealling with someone who does not understand what they are doing or they only want to take on the simplest of projects. Bird Guarding products that don't require drilling into the panels are widely available and have been for some time. The cost is negligible compared to the overall cost of the system and remedial work due to bird damage is expensive.
  • If you intend to have a battery and the sales person is not willing to quote for a system that provides at least a couple of sockets for use during a power outage then move on. There is some extra cost and complexity involved, but it should not be prohibitive. Again, you are dealing with someone who does not have the customers' best interests in mind. In the UK power outages are currently rare, but when we start having them you will wish you could use your system in this way.
  • If your sales person absolutely won't consider systems over 3.8kWp, then they simply don't want the hassle of doing a G99 application. If your property and usage patterns warrant a larger system, they will be selling you a system unsuited to your needs.

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