There are many ways to generate electricity and heat for the home from renewable zero and low carbon sources which can help us tackle the climate emergency.
It's also much easier to get permission to amend your home to make use of renewable energy following the amendment of the general permitted development order.
Solar photovoltaics
Solar photovoltaics (PV) are panels that use the sun to create electricity. They don’t need direct sunlight to work and can generate electricity when it’s cloudy.
In housing, the panels are normally placed on a south facing roof (although they can be used on south–east or south-west facing roofs without losing too much efficiency). The panels are wired through an inverter which will convert the electricity produced from AC to DC.
This in turn is connected to a generation meter which will tell you how much electricity they have produced. This will then normally feed into the National Grid. This allows the power generated to be sold to the grid and be used by someone else if you aren’t using it.
If you are not on the National Grid you will need batteries to save the energy produced. You will need around 10m2 of shade free space to install panels.
There are different types of solar panels. You can generally choose between mono-crystalline or poly-crystalline panels and these panels can be made as solar roof tiles or conventional bolt-on panels.
Mono-crystalline is more efficient but more expensive. Individual panels or tiles are clipped together to create a “solar array”. One kilowatt of panels would produce around 750-800 kilowatt hours of electricity.
The average household uses around 3,300 kilowatt hours of electricity. An average roof would normally hold enough panels to create a quarter to a half of the energy used in the house.
Maintenance
The panels themselves should be virtually maintenance free. They need to be kept clean but the rain should take care of that. You may need to replace the inverter every 5 to 10 years.
Costs
PV systems can vary significantly in price. There is no feed in tariff from government for new solar panel installations which may make new solar panel installations less financially viable. A replacement scheme the Smart Export Guarantee exists, however, this only pays you for excess energy which you generate and export to the national grid.
The cost depends on the amount of panels used, the size of the panels and various other issues. We would recommend you get at least 3 quotes before deciding which company to use.
When the feed in tariff existed some companies offered “free” solar schemes where there would be no upfront cost of getting solar panels installed, but the company would receive your payments from the feed in tariff. If you are considering a scheme of this nature it is important that you understand what you are signing up to. Some schemes involve “renting your roof” to companies, which may affect your ability to sell your property in the future.
Solar hot water
Solar thermal systems (collectors) use the sun to heat water, which is stored in your hot water cylinder. It can provide up to 70% of a family’s domestic hot water usage, with more in summer than winter.
The panels are usually low profile and are not normally suitable to provide heating as they can only generate this amount of heat in the summer when heating isn’t normally required.
There are 2 different types of panels, flat plate and evacuated tube:
- flat plates consist of a flat “radiator” absorber, covered by glass and insulated. Their efficiency depends on the insulation properties and type of construction
- evacuated tubes are a lot more efficient. Water is passed through an evacuated glass tube, which contains a black absorber plate. Since these are very efficient, only a small area is required. These are more expensive than the flat plate system
Maintenance
Most systems will require little maintenance. They should be visually checked once a year and inspected by an accredited installer every few years.
Biomass
Biomass is natural fuel normally used to generate heat and sometimes electricity. In most cases the fuel will be wood, either chipped, in logs or pellets. These can be burnt in either a room heater or a boiler.
A very important factor to consider before installing a solid fuel burner is that Sheffield is covered by the Clean Air Act. This means that it is illegal to burn fuel that emits smoke unless it's in an approved appliance and you could be fined £1,000.
In Sheffield all biomass boilers, room heaters and any type of wood burners must be on the Exempt Fireplaces List to be used under the Clean Air Act.
Biomass boilers will normally require space for a fuel store and even a room heater will require a dry space to store your fuel.
Maintenance
You should refer to the operating manual of your own biomass boiler but, generally, biomass boilers will need more maintenance than gas boilers. They will need to be visually checked every day and in a lot of cases will need the fuel store to be filled by hand.
The ash cans will need emptying every week, the grate will need to be checked every month to ensure there are no blockages and the boiler will need a full yearly service.