Is it time to say goodbye to oil?
Our recent survey told us something we already knew, that the vast majority of households in Hook Norton rely on oil for heating. At the moment, with low oil prices, that maybe doesn’t look to be such a bad deal, but history suggests oil prices are volatile. Members of the Oil Syndicate (by no means every oil user in Hook Norton) used 750,000 litres of oil last year, which took 95 tanker journeys to deliver.
As you will have guessed from our name, cost isn’t the only thing we are worried about when you are heating your home. Heating the average house by oil also creates nearly 3 tonnes of carbon dioxide emissions. You would have to drive your car 12,000 miles to do the same amount of damage to the environment.
In reality, it would be difficult to make an economic case for replacing your new, A-rated oil boiler with any form of “green” technology, but if your boiler is old, inefficient, and getting towards the end of its life, it’s maybe time to think of new technologies.
STOP – before you get carried away, it’s worth pointing out that every penny you spend on heating is heat lost from your home. Some heat loss is good, otherwise we would cook ourselves but do you really want to spend all that money, just to heat the air outside your house? So, before you do anything about heating technology, you really should get your house insulated to the maximum practical level. HNLC offer loans for insulation, interest free in certain circumstances.
So, you now have a super insulated home, so you are now spending less on heating, but you still want to pass on a liveable world to your grandchildren. Changing to gas isn’t an option here, so we are left with electric heating or biomass (wood based) heating. Your traditional electric fire is not a good way to heat your house, as electricity is the most expensive fuel per unit of heat, and also has the highest carbon dioxide per unit, though you can offset some of this by buying your electricity from a company that produces electricity from renewable sources.
Electric storage radiators and electric storage boilers use the cheaper electricity available on the economy 7 tariff – but your daytime electricity is then more expensive, so, in carbon terms they are no better than a fan heater.
Heat pumps are different. It sounds like magic, but by using the technology found in your fridge, but in reverse, they harvest heat from the ground, or surrounding air, and pump it into your house. They use electricity to do this, but for every kilowatt that they consume doing that job, you get around three kilowatts of heat. So, suddenly the expense and carbon emissions are cut to a third of what they were. Nothing comes for free, and a typical ground source heat pump installation will cost between £13,000 and £20,000. Air source is a little less efficient, but £7,000 to £11,000 to install. You may have to factor in larger radiators as the output water temperature from heat pumps is lower than from an oil boiler.
Biomass heating starts with your lovely log fire in the inglenook of your cottage, but although wood is a renewable source of energy, it takes time to regrow, so burning wood that way is far from efficient (around 20%). Modern wood burning stoves are many times better than that, but logs are not a cheap fuel, and transporting them uses other fuels. For domestic use, wood pellet boilers are more efficient, and easier to use. They can be totally automatic, but automatic fuel delivery makes for a very bulky installation, which may not be practical, and although you don’t need to feed pellets in that often, you do need to be able to lift them up and pour them in, which could be a challenge for some. The good news is that biomass boilers will usually work fine with your existing radiators and pipework, as they generate similar temperatures to an oil boiler. Typical installations cost from £9,000 to £21,000.
Solar energy usually makes people think of PV panels making electricity on your roof, but government subsidies have been cut, and without them it is difficult to make a financial case for domestic PV at present.
However, a technology that has been around much longer is solar thermal, which is heating your hot water from the sun. Of course, you’re not going to get a tankful of hot water on a dull winters day, but for many months of the year a solar panel on your south facing roof will provide some, and in the summer, all of your hot water – for free – completely free, no carbon, no money (ok, the pump will use a little bit of electricity – but some systems use PV to power the pump!). Installation, £3000 to £5000.
So what is RHI? Heat pumps, biomass boilers and solar thermal panels all attract government subsidy via the Renewable Heating Incentive. It’s relatively easy to claim, and is a very good deal. You need to have an energy assessment done, and that will show the theoretical energy consumption of your home, this is then used to determine the amount of money you get, depending on the technology. For new applicants in July 2016 the figures are Biomass 4.68p per kWh, Air Source Heat Pump 7.51p per kWh, Ground Source Heat Pump 19.33p per kWh and Solar Thermal 19.74p per kWh – the payments run for seven years, is paid quarterly, and in of one of our case studies “Hare Cottage” the RHI is currently covering the total cost of electricity for that property.
So, despite the low oil price (at the moment) now may still be time to move to a low carbon heating technology.