Day 5 – Big Bagnor Household

13 January 2015

I mentioned solar thermal in my last blog. I hasten to add here that there are much better informed people on this subject out there, but as several people have asked for a simple explanation of what we are doing at The Watermill, here we go…

Solar panels are now becoming a more familiar sight on roofs (and in fields). What some may not know is they come in two forms: PV (photo voltaic) and solar thermal – as Miranda’s friend would say, “bear with”, I’ll try and make this painless.

Solar thermal is a panel that we are going to pump water through. We will harvest heat energy from the sun to warm the panel, which in turn heats the water up (see that didn’t hurt). Now, many think this may not be of much use in everyday life – having warm water when it is sunny – but for us, the potential is great.

If you boil a kettle with cold water, it uses a lot more energy and therefore costs more than if you start with warm water. This, put simply, is what the panels will do for us; warm up the water before it gets to our boilers for the hot water we use. Therefore, it will take less energy to get it as hot as we want.

Again, many will say “what use is that during the day?” Well yes, most of our shows are at night, but Grahame and Lee, our chefs, are in every day preparing all the meals for the restaurant. Therefore, we use a large amount of hot water during the day, hence our excitement at what it may save for us.

The other solar panels, PV, are the more common ones and produce electric power. Again, we can be flummoxed when we hear things like ‘it’s a 1k array’. This simply means the combined power from all the panels in full sun could produce a maximum of 1 kilowatts – (which, if you are old enough, is the same amount of energy used by a single bar on an electric fire) and this is the standard unit cost for electricity. Therefore, it means if you have a 3k system and it’s a sunny day you can boil a kettle, have a cup of tea and it will cost nothing.

We are looking at putting both types of panels on our roofs, though the solar thermal will be the first. I hope this has helped to explain a little of what we are doing.

Lawrence T Doyle
Production Manager