by ericmark »
Tue Sep 08, 2015 8:24 pm
There are many ways to use the economy 7 tariff in the beginning we had the white meter and that only turned on at set times but there was a move away from that system so you can set washing machine for example to use the off peak supply.
So we started to see duel timers one for the electric company and one for the user and also massive bills where the two did not switch at same time.
There have been so many systems that today we have to be really careful to my mind I liked the white meter it gave us no surprise bills.
There were some council houses near here built to use off peak heating with a large heat store in centre of house well insulated with fans and ducts to deliver the heat as and when required. The heat store would stay hot for a week if fans not used and it worked well.
Today we have a similar design using water again very well insulated the water store can actually be outside.
However in the main the bricks in heater type of off peak heating has been a failure.
We talk about heater efficiency if you want heat for one hour and it takes the heater one hour to heat the room that heater is 50% efficient if it takes just 1/2 hour it's 75% efficient. If the heater takes 7 hours to heat up and gives out heat for 24 hours when you only want it for 6 hours then the efficiency is really poor. Many find cheaper running without the economy 7 tariff because then power in the day is cheaper.
For an office heat wanted 9 - 5 the economy 7 tariff worked well. With a home with children and wife at home all day the economy 7 tariff was reasonable. But out to work at 8 and return at 6 and the economy 7 tariff simply does not work unless you use one of the special heat stores which when off loose very little heat.
But the heat store is very expensive and to pay £3000 to have one fitted it will take many years to get that money back. The ones I have seen combine solar panels, wood burner and off peak and were installed when the house was built. I have not seen one fitted at a latter date. So the money was borrowed on the mortgage so the interest on money borrowed to fit system was low.
Reason for ramble was it is easy to get rid of economy 7 tariff and have all only supply points to heaters turned into sockets. But to just swap one socket is not that easy.