Smart peak rates

SIR – Electricity suppliers charge larger business users 40p per kwh between 5pm and 7pm Monday to Friday. Smart meters will allow suppliers to charge domestic customers similarly, to flatten demand for both generation and distribution. Christopher Mann

Taunton, Somerset

SIR – Every morning I record my smart meter readings on a spreadsheet. I can compare daily, weekly and annual usage and can see the results both numerically and graphically.

I am pleased to be able to claim a saving of £10 a year by reducing the setting on my hot water thermostat.

I suspect the computer costs and social embarrassment of doing this daily make the saving insignificant. Graeme Williams

Kings Hill, Kent

SIR – Mike O’brien was an energy minister a decade ago (“How the smart meter roll out became such an expensive failure its own minister has thrown his out”, report, July 28). He has clarified that he was not referring to a smart meter at all, but an old-fashioned “clip-on” device that wasn’t even connected to an energy supplier and was of dubious accuracy, so I don’t blame him for removing it. I had a similar device in 2006, and removed it a year later.

Smart meters are different. They are the building blocks of a smart energy system fit for the 21st century. They put people in control by giving accurate bills and information on energy use, and they will ensure consumers can get the best deal.

That’s why 11 million households have chosen to have a smart meter installed, and nearly half a million are being installed every month – and eight out of 10 of those people would recommend it to friends and family. Claire Perry MP (Con)

Minister for Energy and Clean Growth London SW1

SIR – The letter from Dr Jonathan Marshall of the Energy and Climate Intelligence Unit (August 1) has a flaw. He mentions suppliers’ savings “that will be passed on to consumers”. Paul Warrener

Forres, Moray

SIR – There is a parallel in the case of water. The Isle of Wight gets all its water from the mainland and some years ago it was decided to meter the whole of the island with the intention of reducing consumption. This proved so effective that the water company lost money. So it put the price up. Duncan Bradbury

Bristol