Renewable energy for the home

Renewable energy for the home

Lots of us are bemused and confused about what renewable energy products are suitable for our homes and what the gains of installing them are. Carl Benfield of Prescient Power in Leicestershire aims to enlighten us

We are becoming familiar with solar panels
Renewable energy is a minefield of confusing facts and figures, it must be said. Lots of us think it's only really relevant for farmers and big business - and would cost far too much for ordinary folks in ordinary houses. Well, think again, says Prescient Power's Carl Benfield, who thinks the future is about renewables. *For the latest solar panels recessed into the roof, see Romag

Back to basics - what is renewable energy?

Renewable energy is a means of generating heat or electricity from the sun, wind and renewable plants, namely trees. There are six main types of mainstream land-based renewable energy:
 
Electricity
Solar panels - converting light to electricity using photovoltaic cells. Placed on roofs, suitable for domestic properties.
Wind turbines - positioned in a favourable location and using rotation to create electricity. Not suitable for domestic properties.
Hydroelectric power - based in a stream and using kinetic energy to generate electricity. Not suitable for householders unless you have a mightly river flowing through your land.
 
Heat
Biomass boilers - using wood pellets, chips or logs as fuel to heat radiators and water. Suitable for larger domestic houses, not good for terraced city houses.
Solar thermal panels - using sunlight to heat water. These are placed on roofs. Suitable for individual domestic houses.
Heat pumps - extracting heat from the ground, air or water. Ground source and air source heat pumps are suitable for residential properties, the former need reasonable sized gardens.
 
So, typically, solar panelsbiomass boilers, solar thermal systems and heat pumps are most relevant for domestic properties.
 
Many of us are familiar with the first three, but less clear about heat pumps. So a ground source heat pump uses pipes which are buried in the garden to extract heat from the ground, which can then be used to heat radiators, underfloor or warm air heating systems and hot water in your home. The pump circulates a mixture of water and antifreeze around a loop of pipe – called a ground loop –  buried in the garden. Heat from the ground is absorbed into the fluid and then passes through a heat exchanger into the heat pump.
 
Air source pumps can be fitted to the exterior of a property and take in air from outside. For more info see here.
 
Each type of renewable energy has its pros and cons and choice depends on factors such as the building type, its location, age and aspect - as well as any preservation or listed status.  
 
Trees from managed forests are sustainable. Biomass boilers generate heat  for homes using wood pellets
A huge amount of energy reaches us from the sun. We're getting better at harnessing it.
Tank to store hot water heated via a biomass boiler
Make heat from wood. A flue from a biomass boiler on the outside of a house
A biomass boiler. You'll be relieved to know they're not all this size, but you do need to live in a fairly large property with a cellar or a space to put one
A plan for a renewable energy equipped house from Prescient Power
Why install renewable energy products?
 
To save money on energy bills (electricity, gas, oil, LPG, coal)
To bring in some additional money
To protect against unpredictable fossil fuel price rises
To do your bit for the environment by decreasing carbon emissions
 
Of course money aspect is still the biggest driver for most of us.  Energy bills are set to continue to rise, and as long as we depend on fossil fuels for the majority or our grid-supplied electricity and heating, we can expect further fluctuations in price due to the volatile nature of oil trading.
 
Making it worthwhile: Feed-In Tariff (FiT) and the Renewable Heat Incentive (RHI)
 
To encourage people to generate heat and electricity at home - what's called micro-generation - the Government has backed two main initiatives: the Feed in Tariff (FiT) and the Renewable Heat Incentive (RHI).
 
FiT is paid through your utility provider as an amount for every unit of electricity that you can generate through solar panels. Even when you use this electricity within your own home you are still paid for the generation and anything extra is fed back to the National Grid for an additional payment.
 
The rate is fixed, index linked and lasts for 20 years.
 
The Renewable Heat Incentive for domestic users is due to launch in this spring, will be paid directly by the Government and looks likely to consist of fixed payments for every unit of heat generated from renewable sources and will likely pay out for seven years.  
 
The aim of both initiatives is to pay for the cost of buying and installing renewable energy, enabling homeowners to reduce their bills and rely less on centrally generated and/or distributed energy. 
 

 

Solar thermal panels generate hot water from daylight and are one of the most cost effective forms of renewable energy
Bio mass boilers make sense for larger properties, and you would need somewhere to store the wood
Green Party MP Caroline Lucas supports drives to get more of us to opt for renewable heat
A visual of how a ground source heat pump system might look
We rail against wind turbines but perhaps it won't be long before communities embrace them for local energy generation
We should all consider whether renewable energy is something worth investing in to help cut carbon emissions
In many cases schemes end up generating a net monetary benefit for the homeowner, in addition to the money saved on bills. Energy Minister Greg Barker says solar panels are proving a better investment than pensions for this very reason, currently offering between five and eight per cent returns, which is arguably better than many investment options.
 
Not forgetting renewable heat, burning wood as pellets or chips in a biomass boiler is five times cheaper than relying on electric heating; so if you use a heating fuel other than gas (including oil or LPG) you would be much better off just on energy bill savings alone.
 
How Much? 
 
The most important thing to consider with renewable energy is the much-talked about ‘payback’.  That means how long it will take for your installation to pay for itself through energy savings and incentive payments.  
 
The more effective the technology is for your property, the faster the payback. For example, an owner with a large, older house with an oil boiler could install a relatively expensive biomass boiler, but in the light of high oil bills, the boiler could pay for itself within four years, leaving 20 or so more years of cheaper energy bills.
 
Again with solar panels, a modern home installing one of the cheaper systems could see payback within seven years - and you can now have panels installed for around £5,000 for an 'average' three-bedroom house.
 
Funding your installation 
 
Paying up front makes the most financial sense, but adding to your mortgage or taking out a loan can be sensible options.  
 
The government's Green Deal does offer some benefits - but be careful as you can almost always find cheaper loan rates elsewhere.
 

 

It's estimated a million UK houses could be fitted with solar panels to generate electricity by 2015
Solar panels to provide hot water for a home
The Energy Saving Trust has detailed information on various forms of renewable energy, as do companies such as Prescient Power
How solar power works - a useful info graphic
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So what would I need to do? 
 
Firstly, do not even think about renewable energy until you have done all you can to reduce your energy usage through efficiency measures.  These include insulating your roof, walls and floors, switching to energy efficient light bulbs and making sure your windows and doors are draught free and, ideally, double glazed. 
 
And change your behaviour at home - turn down your thermostat by one degree when you're in, and and put heating off when you're out. Turn off lights when you leave a room and never leave appliances on standby.
 
Once you've done all of these, you should have a good idea of where you use the most energy - heating (which is probably the case if you not using gas) or electricity consumption.   
 
Step two:  contact a local renewable energy installer, preferably a company that offers a range of technologies. They’ll need to visit you at home to have a good look at your property so they can advise you properly. Don't agree to anything over a phone call.
 
Ask friends for recommendations, read installers' websites thoroughly, especially their case studies and ask to talk to the people featured in them - a good installer will have a bank of happy customers willing to discuss their experience.
 
There are accreditation schemes such as MCS (Microgeneration Certification Scheme)HETAS and RECC (Renewable Energy Consumer Code) which offer peace of mind that the installer has passed various inspections and meets standards set by these official organisations.
 
The installers should have the knowledge to help you with planning applications (should you need them) and applications for your incentives. And most importantly, they should be able to justify a system with a short payback period, a good return over 20 years, great savings on your energy bills, and your projected carbon savings.
 
Remember, renewable energy isn’t for everyone
 
If the figures don’t add up, keep up your efficiency measures at home and look to invest your money elsewhere.   
 
But for many of us, renewable energy may well prove to be the best investment we make.
 
*See our piece on the new Tesla Powerwall2 storage battery that works with your PV panels
 
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