Insulating your hot water cylinder is one of the simplest and easiest ways to save energy and money. Fitting a British Standard 'jacket' around your cylinder will cut heat loss by over 75%. If you already have a jacket fitted, check that it's at least 75mm thick. If not, it's well worth treating your old cylinder to a new winter coat.
How tank and pipe insulation works
Both tank and pipe insulation keep your water hotter for longer by reducing the amount of heat that escapes.
The savings
A new, 80mm thick hot water cylinder jacket will save you £20 per year. The jackets themselves cost about half that, meaning that you'll reclaim your initial cost in around 6 months. Insulation for hot water pipes will cost about £10 and save you around £10 a year, which means you could potentially recover the cost of fitting within a year.
You'll be saving about 150kg of CO2 when you fit a British standard hot water cylinder jacket and about 60kg of CO2 with pipe insulation.
The following table gives approximate costs, savings and paybacks for hot water cylinder jackets and pipe insulation:
