Is it cheaper to have a bath or a shower? Your energy questions answered

theguardian.com:

With energy bills on everyone’s mind, those little questions about how to cut your use have come to the fore. We asked experts to answer some FAQs.

The million-dollar question. Brian Horne, a senior insight and analytics consultant at the Energy Saving Trust, says a kettle is more efficient than a hob for heating water as it is heated from the inside, whereas the pan is heated from the outside and needs to get warm first. Kettles will boil water faster and use fewer units of energy. But while gas hobs take much longer and use up to three times more energy in unit terms, the consumer group Which? says that because gas is cheaper than electricity (less than a third per unit), it works out slightly cheaper to boil water on a gas hob than using an electric kettle. This assumes you are boiling only the quantity you need, are using a lid and switch off the hob as soon as it has boiled.

Yes. British Gas estimates that as much as 23% of our electrical usage, or £200 a year currently, could be put down to what are being termed vampire devices – chargers left plugged in and switched on or items on standby. Hi-fis, televisions, set-top boxes and games consoles that sit on standby are all using power – and the older the device, the greater the standby load. However, it is also the unseen chargers, such as those for electric toothbrushes, razors, etc. “As soon as your device is fully charged, try to get into the habit of unplugging it,” says Marc Robson, a British Gas smart energy expert. “As well as saving energy, this will prolong your battery life. And it could also save you about £60 a year on your electricity bills.”

Gas, because the unit price is far less than the unit price of electricity. This is partly offset if you have an