Generating your own energy is probably the way of the future and you can start doing it now.
There are 7 key options: wind turbines, solar water heating and solar electricity, ground source and air source heat pumps, wood fuelled heating and hydro power.
Various grants of up to £2500 are also available to encourage home owners to generate their own power.
So to help you decide if this is for you, here is a quick look at the options;
1. WIND TURBINES harness the power of the wind using it to generate electricity. Small systems called “microwind” or “small-wind” turbines can produce electricity to help power lights and electrical appliances in a typical home.
Its worth noting that 40% of all the wind energy in Europe blows over the UK, making it an ideal country for small domestic turbines.
Wind turbines use large blades to catch the wind. When the wind blows the blades are forced round, driving a turbine which generates electricity. The stronger the wind, the more electricity produced.
There are two types of domestic-sized wind turbine:
> Mast mounted:these are free standing and are erected in a suitably exposed position, often around 2.5kW to 6kW
> Roof mounted: these are smaller than mast mounted systems and can be installed on the roof of a home where there is a suitable wind resource. Often these are around 1kW to 2kW in size.
If your small wind system is connected to the National Grid then you can make money by selling any generated electricity to an electricity supply company.
If the turbine is not connected to the electricity grid then unused electricity can be stored in a battery for use when there is no wind.
There are a number of benefits of wind generated electricity;
> Harnessing a plentiful energy source
> Cutting your carbon footprint: wind electricity is green, renewable and doesn’t release any harmful carbon dioxide or other pollutants
> Cutting your electricity bills: wind is free, so once you’ve paid for the initial installation your electricity costs will be reduced
> Store electricity for a calm day: if your home isn’t connected to the National Grid you can store excess electricity in batteries and use it when there is no wind.
2. SOLAR WATER HEATING systems use heat from the sun to warm domestic hot water. A conventional boiler or immersion heater is then used to heat the water further or provide hot water when solar energy is unavailable.
Solar water heating systems use solar panels, called collectors, fitted to your roof. These collect heat from the sun and use it to warm water which is stored in a hot water cylinder.
There are two types of solar water heating panels; evacuated tubes and flat plate collectors.
Flat plates collectors can be fixed on the roof tiles or integrated into the roof.
A boiler or immersion heater can be used as a back up to heat the water further to reach the temperature set by the cylinders thermostat when the solar water heating system does not reach that temperature.
Larger solar panels can also provide energy to heat your home as well – though usually only in the summer months when home heating is unnecessary.
The benefits of solar water heating are;
> Hot water throughout the year: the system works all year round, though you’ll need to heat the water further with a boiler or immersion heater during the winter months.
> Cut your bills: sunlight is free, so once you’ve paid for the initial installation your hot water costs will be reduced.
> Cut your carbon footprint: solar hot water is a green, renewable heating system and doesn’t release any harmful carbon dioxide or other pollutants
3. SOLAR ELECTRICITY systems capture the sun’s energy using photovoltaic (PV) cells. The cells convert the sunlight into electricity, which can be used to run household appliances and lighting.
PV cells don’t need direct sunlight to work – you can still generate some electricity on a cloudy day.
PV cells are panels you can attach to your roof or walls. Each cell is made from one or two layers of semiconducting material, usually silicon. When light shines on the cell it creates an electric field across the layers. The stronger the sunshine, the more electricity is produced.
PV cells come in a variety of shapes and colours, from grey “solar tiles” that look like roof tiles to panels and transparent cells that you can use on conservatories and glass.
The strength of a PV cell is measured in kilowatt peak (kWp) – the amount of energy the cell generates in full sunlight.
The are a number of benefits of solar electricity;
> Cut your carbon footprint: A typical home PV system could save around 1200 kg of carbon dioxide per year – that’s around 30 tonnes over its lifetime.
> Cut your electricity bills: A typical home PV system can produce around 40% of the electricity a household uses in a year.
> Sell electricity back to the Grid: if your system is producing more electricity than you need, or when you can’t use it, someone else can use it – and you could make a bit of money.
Store electricity for a cloudy day: if your home isn’t connected to the national grid you can store excess electricity in batteries to use when you need it.
4. AIR SOURCE HEAT PUMPS absorb heat from the outside air even when the temperature is as low as minus 15° C. This heat is used to warm water for radiators or underfloor heating systems, or to warm the air in your home.
There are two main types:
> An air-to-water system uses the heat to warm water. Heat pumps heat water to a lower temperature than a standard boiler system would, so they are more suitable for underfloor heating systems than radiator systems.
> An air-to-air system produces warm air which is circulated by fans to heat your home.
The efficiency of air source heat pump systems is measured by a coefficient of performance (CoP) – the amount of heat they produce compared to the amount of electricity needed to run them. A typical CoP for an air source heat pump is around 2.5.
The benefits of air source heat pumps;
> Reduce your fuel bills: air source heat pumps run on electricity, so there’s no need to pay for gas, oil or solid fuels to heat your home.
> Cut down on wasted electricity: heating your home with an air source heat pump is much more efficient than using electric radiators.
> Save space: an air source heat pump system is compact, and requires no storage space for fuel.
5. GROUND SOURCE HEAT PUMPS use pipes buried in the garden to extract heat from the ground. This is usually used to warm water for radiators or under-floor heating systems. It can also be used to pre-heat water before it goes into a conventional boiler.
Beneath the surface, the ground stays at a constant temperature, so a ground source heat pump can be used throughout the year – even in the middle of winter.
A ground source heat pump circulates a mixture of water and antifreeze around a loop of pipe – called a ground loop – which is buried in the garden. When the liquid travels around the loop it absorbs heat from the ground.
And these are the benefits of ground source heat pumps;
> Reduce your CO2 emissions: on average a ground source heat pump could save around 540kg of carbon dioxide every year when replacing an oil boiler.
> Eliminate your fuel bills: ground source heat pumps run on electricity, so there’s no need to pay for gas, oil or solid fuels to heat your home.
> Cut down on wasted electricity: heating your home with a ground source heat pump is much more efficient than using electric radiators.
6. WOOD FUELLED HEATING SYSTEMS generally burn wood pellets, chips or logs to power central heating and hot water boilers or to provide warmth in a single room.
There are two main ways of using wood to heat you home:
> A standalone stove burning logs or pellets to heat a single room. Some can also be fitted with a back boiler to provide water heating as well.
> A boiler burning pellets, logs or chips connected to a central heating and hot water system.
Log burning stoves and boilers have to be filled with wood by hand. Some pellet and chip burners use automatic fuel feeders which refill them at regular intervals from fuel storage units called hoppers.
The benefits of wood fuel heating are;
> A low carbon option: the carbon dioxide emitted when wood fuel is burned is the same amount that was absorbed over the previous months and years as the plant was growing. As long as new plants continue to grow in place of those used for fuel, the process is sustainable. There are some carbon emissions caused by the cultivation, manufacture and transportation of the fuel, but as long as the fuel is sourced locally, these are much lower than the emissions from fossil fuels.
> A good use for waste wood: burning wood can be a convenient means of disposing of waste that might otherwise be sent to a landfill site.
7. HYDROELECTRICITY SYSTEMS generate electricity from running water – usually a small stream. Small or “micro” hydroelectricity systems can produce enough electricity for lighting and electrical appliances in an average home.
Hydroelectricity systems are also called hydro power systems or just hydro systems.
Hydro power systems use running water to turn a small turbine which generates electricity. The faster the water flows and the more water there is, the more electricity can be generated.
The amount of electricity a system actually generates depends on how efficiently it converts the power of the moving water into electrical power.
Hydropower is not suitable for every home but for those homes that do have access to the appropriate water supply there are a number of benefits;
> Cut your carbon footprint: hydroelectricity is green, renewable energy and doesn’t release any harmful carbon dioxide or other pollutants
> Cut your electricity bills: hydroelectricity is free, so once you’ve paid for the initial installation you’ll reduce or even eliminate your electricity bills
> A lower cost option: installing a hydro system can be expensive, but in many cases it’s less than the cost of getting a connection to the National Grid
> Cheap heating and hot water: a hydro system may generate more electricity than you need for lighting your home and powering your electrical appliances – so you can use the excess to heat your home and your hot water too
If generating your own power is something you’d like to explore further then The Energy Saving Trust website (www.energysavingtrust.org.uk) has a simple questionnaire to help you narrow down your options.
And you can hear more about renewables on PASSION for the PLANET (www.passionfortheplanet.com)