Should I consider alternative sources for the energy to run my home?
Its Green, it’s fashionable, it will save the planet and they say it will save us money so why aren’t we queuing up for it?
What exactly are we talking about?
We live in a world where we are using up finite resources to provide our energy and unless we stop relying on carbon fuels we will turn our planet into an airless moon that will not sustain life as we know it.
The latest oil spill tragedy in the Gulf of Mexico has highlighted even to the energy hungry USA just how fragile is our eco structure.
But what are the alternatives of renewable energy that could be considered for the home?
The Sun – Solar
If you are building a new house design techniques can be used to harness the free energy in the sun such as greenhouses and for light.
An Active Water/Air heating system
can be installed to generate low temperature hot water from daylight. These systems are black panels that absorb daylight to heat a liquid (either water directly or an anti-freeze system through a heat exchanger). These systems usually have roof mounted panels and a larger than normal hot water tank to store the heated water. You do need to have space on the roof for the panels to face the East to South to West side of the building.
Photovoltaic (PV) Solar panels
Which are arranged facing South-East to South-West harness sunshine to generate electricity. There are a number of technology options with slightly differing efficiencies (costs are offset against efficiency). The panels supply electric power to an inverter which converts the direct current (DC) generated into alternating current (AC). This can be stored in a battery or you can connect into the grid where you can be paid for the electricity you generate by your local electricity provider.
Wind Power
The moving blades of a wind turbine convert energy from the wind stream which rotates a shaft, mechanically coupled via a gearbox to an electrical generator. This can be linked to batteries or you can connect into the grid where you can be paid for the electricity you generate.
Biomass Fuels
Essentially this is where biological material (wood, straw, energy crops or other organic material) is combusted in a modern burner/boiler to generate heat. The source for energy is usually dried wood (20% water content, wet basis is normally 50%). The resultant available energy for it is 14.4MJ/kg. Suppliers of fuel are limited but a network of existing producers and new sources are becoming available.
Most solid fuel boilers are adaptable to new sources. Wood is the most abundant fuel source and comes in 3 forms; logs, woodchip and pellets. Pellets are the easiest to automatically load the burner with although there is a processing premium applied.
Ground source heat pumps
The ground at 2m below the surface has a fairly constant temperature of around 10°C) and this system involves the use of underground heat stores of heat created by the Sun and heat that is accumulated through the use of a heat pump. The heat pump is the same principle as a refrigerator in reverse: Think of the hot grills on the back of your domestic refrigerator. The underground heat, is accessed by building a trench which involves digging to 2m deep and up to 1m wide, trench and filling 0.4m of trench with sand at various stages, inserting heat coils and backfilling.
So which should we consider?
Solar water heating systems to work alongside your conventional water heater
This technology is well developed with a large choice of equipment to suit many applications.
Benefits
It can provide almost all of your hot water during the summer months and about 50% year round
It reduces your impact on the environment – the average domestic system reduces carbon dioxide emissions by around 400kg per year, depending on the fuel replaced.
Different Types Of System
What best suits your needs depends on a range of factors, including the area of south facing roof, the existing water heating system (e.g. some combi-boilers aren’t suitable) and your budget.
A competent professional installer should assess your situation and discuss with you the best configuration to meet your needs. Please contact info@1staction.com for further information
Solar Water Heating and Your Home
Solar water heating can be used in the home or for larger applications, such as swimming pools.
For domestic hot water there are three main components: the solar panels, a heat transfer system and a hot water cylinder. Solar panels, or collectors, are fitted to your roof. They collect heat from the sun’s radiation. The heat transfer system uses the collected heat to heat the domestic hot water. A hot water cylinder stores the hot water that is heated during the day and supplies it for use later.
Is My Property Suitable for Solar Heating?
Preferably you will need 2-4m2 of Southeast to Southwest facing roof receiving direct sunlight for the main part of the day. You’ll also need space to locate an additional or larger hot water cylinder, if required.
It may be necessary to gain planning permission to allow you to fit a Solar system, especially in conservation areas or on listed buildings. Always check with your Planning Department before you have a system installed.
Cost and Maintenance
The typical installation cost for a domestic flat plate collector system is £2,000 – £3,000. or an Evacuated tube systems will cost £3,500 – £4,500.
You can fit or build the system yourself. But although it may be cheaper it will take longer and you’ll need a certain level of skill. Note however that DIY jobs are not normally eligible for grant funding.
A Solar hot water systems generally come with a 10-year warranty and require very little maintenance. A yearly check by the householder and a more detailed check by a professional installer every 3-5 years should be sufficient. Your supplier will give you exact maintenance requirements.
Solar PV Roof Panels
You can use PV systems for a building with a roof or wall that faces within 90 degrees of south, as long as no other buildings or large trees overshadow it. If the roof surface is in shadow for parts of the day the output of the system decreases.
Solar panels are not light and the roof must be strong enough to take their weight, especially if the panel is placed on top of existing tiles.
Solar PV installations should always be carried out by a trained and experienced installer.
By producing your own electricity you essentially become a supplier yourself. As well as producing electricity for your own needs, there will be times when your system produces more than you need. In this situation, the surplus electricity will be fed into the local network.
It is the responsibility of your chosen installer to ensure your system is installed according to the existing electrical installation regulations. It is also their responsibility to contact the local Distribution Network Operator to advise that a new PV system is being connected in their area.
The connection of PV systems to the electricity grid has become standard procedure and paperwork will likely be dealt with by the installer as part of the service.
Cost and Maintenance
Prices for PV systems vary, depending on the size of the system to be installed, type of PV cell used and the nature of the actual building on which the PV is mounted.
For the average domestic system, costs can be around £4,000- £9,000 per kWp installed, with most domestic systems usually requiring between 1.5 and 2 kWp.
A further option is solar tiles which cost more than conventional panels and also panels that are integrated into a roof are more expensive than those that sit on top.
Planning Considerations
It may be necessary to gain planning permission to allow you to fit a PV system, especially in
conservation areas or on listed buildings. Always check with your Planning Department before you have a system installed
Funding
For Solar PV systems there is grant maximum of £3,000 per kWp installed, up to a maximum of £15,000 subject to an overall 50% limit of the installed cost (exclusive of VAT)
Please note that prior to issue of any grant towards renewables, the BERR will ensure the applicants property has already been made efficient in its energy use.
Small Scale Wind Power and Your Home
Wind speed increases with height so it’s best to have the turbine high on a mast or small tower and generally speaking the ideal site is a smooth hill top hill with a flat, clear exposure, free from excessive turbulence and obstructions such as large trees, houses or other buildings.
However, small-scale building-integrated wind turbines suitable for urban locations have now been developed e.g. ‘Windsave’ and can be sited near to the apex of the roof – similar to an aerial or satellite dish.
Knowledge of the local wind is critical to designing a wind energy system and predicting output. For domestic installations a good source of information on local wind speeds is the NOABL database which can be accessed from the British Wind Energy Association website.
Planning issues such as visual impact, noise and conservation issues also have to be considered.
Please contact info@1staction.com for installation information
Grid-Connected System?
Small scale wind systems can installed where there is a grid connection. A special inverter and controller convert DC electricity to AC at a quality and standard acceptable to the grid. No battery storage is required. Any unused or excess electricity can be exported to the grid and sold to the local electricity supply company.
By producing your own electricity you essentially become a supplier yourself. As well as producing electricity for your own needs, there will be times when your system produces more than you need. It is your installer’s responsibility to contact the local Distribution Network Operator to advise that a new wind energy system is being connected in their area.
The connection of wind energy systems to the electricity grid has become standard procedure and paperwork will likely be dealt with by the installer as part of the service.
Cost and Maintenance
Systems up to 1kW will cost around £3000 whereas larger systems in the region of 1.5kW to 6kW would cost between £4,000 – £18,000 installed. These costs are inclusive of the turbine, mast, inverters, battery storage (if required) and installation, however it’s important to remember that costs always vary depending on location and the size and type of system.
Turbines can have a life of up to 20 years but require service checks every few years to ensure they work efficiently. For battery storage systems, typical battery life is around 6-10years, depending on the type, so batteries may have to be replaced at some point in the system’s life.
Funding
Grant maximum £1,000 per kW installed, up to a maximum of £5,000 subject to an overall 30% limit of the installed cost (exclusive of VAT)
Please note, that prior to issue of any grant towards renewables, the BERR will ensure the applicants property have already been made efficient in its energy use.
Ground Source Heat Pumps
Benefits
The efficiency of a ground source heat pump system is measured by the coefficient of performance (CoP). This is the ratio of units of heat output for each unit of electricity used to drive the compressor and pump for the ground loop. Average CoP over the year, known as seasonal efficiency, is around 3-4 although some systems may produce a greater rate of efficiency. This means that for every unit of electricity used to pump the heat, 3-4 units of heat are produced, making it an efficient way of heating a building. If grid electricity is used for the compressor and pump, then you should consult a range of energy suppliers to benefit from the lowest running costs, for example by choosing an economy 10 or economy 7 tariff.
How It Works
There are three important elements to a ground source heat pump:
Ground Loop
This is comprised of lengths of pipe buried in the ground, either in a borehole or a horizontal trench. The pipe is usually a closed circuit and is filled with a mixture of water and antifreeze, which is pumped around the pipe absorbing heat from the ground. The ground loop can be:
Vertical, for use in boreholes, Horizontal, for use in trenches or a Spiral coil also for use in trenches
Heat Pump
In the same way that your fridge uses refrigerant to extract heat from the inside, keeping your food cool, a ground source heat pump extracts heat from the ground, and uses it to heat your home.
A ground source heat pump has three main parts: 1) The evaporator, (e.g. the coiled element in the cold part of your fridge) absorbs the heat using the liquid in the ground loop; 2) The compressor, (this is what makes the noise in a fridge) moves the refrigerant round the heat
pump and compresses the gaseous refrigerant to the temperature needed for the heat
distribution circuit and 3) The condenser, (the hot part at the back of your fridge) gives up heat to a hot water tank which feeds the distribution system.
Heat Distribution System
This consists of under floor heating or radiators for space heating and in some cases water storage for hot water supply.
Ground Source Heat Pumps and Your Home
You should consider the following issues if you’re thinking about installing a ground source heat pump. An accredited installer will be able to provide more detailed advice.
You will need space outside your house for the ground loop.
The ground will need to be suitable for digging a trench or borehole.
What fuel is being replaced? If it’s electricity, oil, LPG or coal the savings will be more favourable than gas. Heat pumps are a particularly good option where gas is unavailable.
The type of heat distribution system. Ground source heat pumps can be combined with radiators but these will normally be larger than with standard boiler systems. Under floor heating is better as it works at a lower temperature.
Please contact info@1staction.com for further information
Costs
A typical 8 – 12kW system costs £6,000 – £12,000 (not including the price of distribution system). This can vary with property, system size and location. Vertical ground loop systems are significantly more expensive to install than horizontal ground loops, due to the higher cost of drilling a borehole. When installed in an electrically heated home a ground source heat pump could save as much as £1000 a year on heating bills and almost 7 tonnes of carbon dioxide a year. Savings will vary depending on what fuel is being replaced
Funding
For Ground Source Heat Pump systems there is a maximum £1,200 grant, subject to an overall 30% limit (exclusive of VAT).
So why aren’t we queuing to install these alternative fuel systems?
It has to be the issue of installation costs against the savings we could make.
In the long term there will be savings but in a society who changes their homes on average every seven years we cannot expect to get a return on our investment in that time and we don’t really get the added value of the cost of the investment when we sell.
There are grants and loans available to encourage us but not sufficient to make the difference.
The other trouble is that much of the technology is still developing and in this technological world we have come to believe that technology gets cheaper as it develops. We can buy a 42” plasma television now for 25% of the price we would have paid two years ago.
The two systems that are now well tried are the Solar water heating systems that works alongside your conventional water heater costing between £2,000 to £4,500 and Ground Source Heat Pumps which can cost between £6,000 – £12,000
It’s a choice we all can make now and a choice we will no doubt all have to make in the future if we want to keep this wonderful planet that we share.
Should I consider alternative sources for the energy to run my home?
Its Green, it’s fashionable, it will save the planet and they say it will save us money so why aren’t we queuing up for it?
What exactly are we talking about?
We live in a world where we are using up finite resources to provide our energy and unless we stop relying on carbon fuels we will turn our planet into an airless moon that will not sustain life as we know it.
The latest oil spill tragedy in the Gulf of Mexico has highlighted even to the energy hungry USA just how fragile is our eco structure.
But what are the alternatives of renewable energy that could be considered for the home?
The Sun – Solar
If you are building a new house design techniques can be used to harness the free energy in the sun such as greenhouses and for light.
An Active Water/Air heating system can be installed to generate low temperature hot water from daylight. These systems are black panels that absorb daylight to heat a liquid (either water directly or an anti-freeze system through a heat exchanger). These systems usually have roof mounted panels and a larger than normal hot water tank to store the heated water. You do need to have space on the roof for the panels to face the East to South to West side of the building.
Photovoltaic (PV) Solar panels which are arranged facing South-East to South-West harness sunshine to generate electricity. There are a number of technology options with slightly differing efficiencies (costs are offset against efficiency). The panels supply electric power to an inverter which converts the direct current (DC) generated into alternating current (AC). This can be stored in a battery or you can connect into the grid where you can be paid for the electricity you generate by your local electricity provider.
Wind
The moving blades of a wind turbine convert energy from the wind stream which rotates a shaft, mechanically coupled via a gearbox to an electrical generator. This can be linked to batteries or you can connect into the grid where you can be paid for the electricity you generate.
Biomass
Essentially this is where biological material (wood, straw, energy crops or other organic material) is combusted in a modern burner/boiler to generate heat. The source for energy is usually dried wood (20% water content, wet basis is normally 50%). The resultant available energy for it is 14.4MJ/kg. Suppliers of fuel are limited but a network of existing producers and new sources are becoming available.
Most solid fuel boilers are adaptable to new sources. Wood is the most abundant fuel source and comes in 3 forms; logs, woodchip and pellets. Pellets are the easiest to automatically load the burner with although there is a processing premium applied.
Ground source heat pumps
The ground at 2m below the surface has a fairly constant temperature of around 10°C) and this system involves the use of underground heat stores of heat created by the Sun and heat that is accumulated through the use of a heat pump. The heat pump is the same principle as a refrigerator in reverse: Think of the hot grills on the back of your domestic refrigerator. The underground heat, is accessed by building a trench which involves digging to 2m deep and up to 1m wide, trench and filling 0.4m of trench with sand at various stages, inserting heat coils and backfilling.
The Heat Pump in the new offices at The National Energy Foundation
The ground loop being installed in a trench at the National Energy Foundation
So which should we consider?
Solar water heating systems to work alongside your conventional water heater
This technology is well developed with a large choice of equipment to suit many applications.
Benefits
It can provide almost all of your hot water during the summer months and about 50% year round
It reduces your impact on the environment – the average domestic system reduces carbon dioxide emissions by around 400kg per year, depending on the fuel replaced.
Different Types Of System
What best suits your needs depends on a range of factors, including the area of south facing roof, the existing water heating system (e.g. some combi-boilers aren’t suitable) and your budget.
A competent professional installer should assess your situation and discuss with you the best configuration to meet your needs. Please contact info@1staction.com for further information
Solar Water Heating and Your Home
Solar water heating can be used in the home or for larger applications, such as swimming pools.
For domestic hot water there are three main components: the solar panels, a heat transfer system and a hot water cylinder. Solar panels, or collectors, are fitted to your roof. They collect heat from the sun’s radiation. The heat transfer system uses the collected heat to heat the domestic hot water. A hot water cylinder stores the hot water that is heated during the day and supplies it for use later.
Is My Property Suitable?
Preferably you will need 2-4m2 of Southeast to Southwest facing roof receiving direct sunlight for the main part of the day. You’ll also need space to locate an additional or larger hot water cylinder, if required.
It may be necessary to gain planning permission to allow you to fit a Solar system, especially in conservation areas or on listed buildings. Always check with your Planning Department before you have a system installed.
Cost and Maintenance
The typical installation cost for a domestic flat plate collector system is £2,000 – £3,000. or an Evacuated tube systems will cost £3,500 – £4,500.
You can fit or build the system yourself. But although it may be cheaper it will take longer and you’ll need a certain level of skill. Note however that DIY jobs are not normally eligible for grant funding.
A Solar hot water systems generally come with a 10-year warranty and require very little maintenance. A yearly check by the householder and a more detailed check by a professional installer every 3-5 years should be sufficient. Your supplier will give you exact maintenance requirements.
Solar PV
You can use PV systems for a building with a roof or wall that faces within 90 degrees of south, as long as no other buildings or large trees overshadow it. If the roof surface is in shadow for parts of the day the output of the system decreases.
Solar panels are not light and the roof must be strong enough to take their weight, especially if the panel is placed on top of existing tiles.
Solar PV installations should always be carried out by a trained and experienced installer.
By producing your own electricity you essentially become a supplier yourself. As well as producing electricity for your own needs, there will be times when your system produces more than you need. In this situation, the surplus electricity will be fed into the local network.
It is the responsibility of your chosen installer to ensure your system is installed according to the existing electrical installation regulations. It is also their responsibility to contact the local Distribution Network Operator to advise that a new PV system is being connected in their area.
The connection of PV systems to the electricity grid has become standard procedure and paperwork will likely be dealt with by the installer as part of the service.
Cost and Maintenance
Prices for PV systems vary, depending on the size of the system to be installed, type of PV cell used and the nature of the actual building on which the PV is mounted.
For the average domestic system, costs can be around £4,000- £9,000 per kWp installed, with most domestic systems usually requiring between 1.5 and 2 kWp.
A further option is solar tiles which cost more than conventional panels and also panels that are integrated into a roof are more expensive than those that sit on top.
Planning Considerations
It may be necessary to gain planning permission to allow you to fit a PV system, especially in
conservation areas or on listed buildings. Always check with your Planning Department before you have a system installed
Funding
For Solar PV systems there is grant maximum of £3,000 per kWp installed, up to a maximum of £15,000 subject to an overall 50% limit of the installed cost (exclusive of VAT)
Please note that prior to issue of any grant towards renewables, the BERR will ensure the applicants property has already been made efficient in its energy use. Small Scale Wind Power and Your Home
Wind speed increases with height so it’s best to have the turbine high on a mast or small tower and generally speaking the ideal site is a smooth hill top hill with a flat, clear exposure, free from excessive turbulence and obstructions such as large trees, houses or other buildings.
However, small-scale building-integrated wind turbines suitable for urban locations have now been developed e.g. ‘Windsave’ and can be sited near to the apex of the roof – similar to an aerial or satellite dish.
Knowledge of the local wind is critical to designing a wind energy system and predicting output. For domestic installations a good source of information on local wind speeds is the NOABL database which can be accessed from the British Wind Energy Association website.
Planning issues such as visual impact, noise and conservation issues also have to be considered.
Please contact info@1staction.com for installation information
Grid-Connected System?
Small scale wind systems can installed where there is a grid connection. A special inverter and controller convert DC electricity to AC at a quality and standard acceptable to the grid. No battery storage is required. Any unused or excess electricity can be exported to the grid and sold to the local electricity supply company.
By producing your own electricity you essentially become a supplier yourself. As well as producing electricity for your own needs, there will be times when your system produces more than you need. It is your installer’s responsibility to contact the local Distribution Network Operator to advise that a new wind energy system is being connected in their area.
The connection of wind energy systems to the electricity grid has become standard procedure and paperwork will likely be dealt with by the installer as part of the service.
Cost and Maintenance
Systems up to 1kW will cost around £3000 whereas larger systems in the region of 1.5kW to 6kW would cost between £4,000 – £18,000 installed. These costs are inclusive of the turbine, mast, inverters, battery storage (if required) and installation, however it’s important to remember that costs always vary depending on location and the size and type of system.
Turbines can have a life of up to 20 years but require service checks every few years to ensure they work efficiently. For battery storage systems, typical battery life is around 6-10years, depending on the type, so batteries may have to be replaced at some point in the system’s life.
Funding
Grant maximum £1,000 per kW installed, up to a maximum of £5,000 subject to an overall 30% limit of the installed cost (exclusive of VAT)
Please note, that prior to issue of any grant towards renewables, the BERR will ensure the applicants property have already been made efficient in its energy use.
Ground Source Heat Pumps
Benefits
The efficiency of a ground source heat pump system is measured by the coefficient of performance (CoP). This is the ratio of units of heat output for each unit of electricity used to drive the compressor and pump for the ground loop. Average CoP over the year, known as seasonal efficiency, is around 3-4 although some systems may produce a greater rate of efficiency. This means that for every unit of electricity used to pump the heat, 3-4 units of heat are produced, making it an efficient way of heating a building. If grid electricity is used for the compressor and pump, then you should consult a range of energy suppliers to benefit from the lowest running costs, for example by choosing an economy 10 or economy 7 tariff.
How It Works
There are three important elements to a ground source heat pump:
Ground Loop
This is comprised of lengths of pipe buried in the ground, either in a borehole or a horizontal trench. The pipe is usually a closed circuit and is filled with a mixture of water and antifreeze, which is pumped around the pipe absorbing heat from the ground. The ground loop can be:
Vertical, for use in boreholes, Horizontal, for use in trenches or a Spiral coil also for use in trenches
Heat Pump
In the same way that your fridge uses refrigerant to extract heat from the inside, keeping your food cool, a ground source heat pump extracts heat from the ground, and uses it to heat your home.
A ground source heat pump has three main parts: 1) The evaporator, (e.g. the coiled element in the cold part of your fridge) absorbs the heat using the liquid in the ground loop; 2) The compressor, (this is what makes the noise in a fridge) moves the refrigerant round the heat
pump and compresses the gaseous refrigerant to the temperature needed for the heat
distribution circuit and 3) The condenser, (the hot part at the back of your fridge) gives up heat to a hot water tank which feeds the distribution system.
Heat Distribution System
This consists of under floor heating or radiators for space heating and in some cases water storage for hot water supply.
Ground Source Heat Pumps and Your Home
You should consider the following issues if you’re thinking about installing a ground source heat pump. An accredited installer will be able to provide more detailed advice.
You will need space outside your house for the ground loop.
The ground will need to be suitable for digging a trench or borehole.
What fuel is being replaced? If it’s electricity, oil, LPG or coal the savings will be more favourable than gas. Heat pumps are a particularly good option where gas is unavailable.
The type of heat distribution system. Ground source heat pumps can be combined with radiators but these will normally be larger than with standard boiler systems. Under floor heating is better as it works at a lower temperature.
Please contact info@1staction.com for further information
Costs
A typical 8 – 12kW system costs £6,000 – £12,000 (not including the price of distribution system). This can vary with property, system size and location. Vertical ground loop systems are significantly more expensive to install than horizontal ground loops, due to the higher cost of drilling a borehole. When installed in an electrically heated home a ground source heat pump could save as much as £1000 a year on heating bills and almost 7 tonnes of carbon dioxide a year. Savings will vary depending on what fuel is being replaced
Funding
For Ground Source Heat Pump systems there is a maximum £1,200 grant, subject to an overall 30% limit (exclusive of VAT).
So why aren’t we queuing to install these systems?
It has to be the issue of installation costs against the savings we could make.
In the long term there will be savings but in a society who changes their homes on average every seven years we cannot expect to get a return on our investment in that time and we don’t really get the added value of the cost of the investment when we sell.
There are grants and loans available to encourage us but not sufficient to make the difference.
The other trouble is that much of the technology is still developing and in this technological world we have come to believe that technology gets cheaper as it develops. We can buy a 42” plasma television now for 25% of the price we would have paid two years ago.
The two systems that are now well tried are the Solar water heating systems that works alongside your conventional water heater costing between £2,000 to £4,500 and Ground Source Heat Pumps which can cost between £6,000 – £12,000
It’s a choice we all can make now and a choice we will no doubt all have to make in the future if we want to keep this wonderful planet that we share.
Should I consider alternative sources for the energy to run my home?
Its Green, it’s fashionable, it will save the planet and they say it will save us money so why aren’t we queuing up for it?
What exactly are we talking about?
We live in a world where we are using up finite resources to provide our energy and unless we stop relying on carbon fuels we will turn our planet into an airless moon that will not sustain life as we know it.
The latest oil spill tragedy in the Gulf of Mexico has highlighted even to the energy hungry USA just how fragile is our eco structure.
But what are the alternatives of renewable energy that could be considered for the home?
The Sun – Solar
If you are building a new house design techniques can be used to harness the free energy in the sun such as greenhouses and for light.
An Active Water/Air heating system can be installed to generate low temperature hot water from daylight. These systems are black panels that absorb daylight to heat a liquid (either water directly or an anti-freeze system through a heat exchanger). These systems usually have roof mounted panels and a larger than normal hot water tank to store the heated water. You do need to have space on the roof for the panels to face the East to South to West side of the building.
Photovoltaic (PV) Solar panels which are arranged facing South-East to South-West harness sunshine to generate electricity. There are a number of technology options with slightly differing efficiencies (costs are offset against efficiency). The panels supply electric power to an inverter which converts the direct current (DC) generated into alternating current (AC). This can be stored in a battery or you can connect into the grid where you can be paid for the electricity you generate by your local electricity provider.
Wind
The moving blades of a wind turbine convert energy from the wind stream which rotates a shaft, mechanically coupled via a gearbox to an electrical generator. This can be linked to batteries or you can connect into the grid where you can be paid for the electricity you generate.
Biomass
Essentially this is where biological material (wood, straw, energy crops or other organic material) is combusted in a modern burner/boiler to generate heat. The source for energy is usually dried wood (20% water content, wet basis is normally 50%). The resultant available energy for it is 14.4MJ/kg. Suppliers of fuel are limited but a network of existing producers and new sources are becoming available.
Most solid fuel boilers are adaptable to new sources. Wood is the most abundant fuel source and comes in 3 forms; logs, woodchip and pellets. Pellets are the easiest to automatically load the burner with although there is a processing premium applied.
Ground source heat pumps
The ground at 2m below the surface has a fairly constant temperature of around 10°C) and this system involves the use of underground heat stores of heat created by the Sun and heat that is accumulated through the use of a heat pump. The heat pump is the same principle as a refrigerator in reverse: Think of the hot grills on the back of your domestic refrigerator. The underground heat, is accessed by building a trench which involves digging to 2m deep and up to 1m wide, trench and filling 0.4m of trench with sand at various stages, inserting heat coils and backfilling.
The Heat Pump in the new offices at The National Energy Foundation
The ground loop being installed in a trench at the National Energy Foundation
So which should we consider?
Solar water heating systems to work alongside your conventional water heater
This technology is well developed with a large choice of equipment to suit many applications.
Benefits
It can provide almost all of your hot water during the summer months and about 50% year round
It reduces your impact on the environment – the average domestic system reduces carbon dioxide emissions by around 400kg per year, depending on the fuel replaced.
Different Types Of System
What best suits your needs depends on a range of factors, including the area of south facing roof, the existing water heating system (e.g. some combi-boilers aren’t suitable) and your budget.
A competent professional installer should assess your situation and discuss with you the best configuration to meet your needs. Please contact info@1staction.com for further information
Solar Water Heating and Your Home
Solar water heating can be used in the home or for larger applications, such as swimming pools.
For domestic hot water there are three main components: the solar panels, a heat transfer system and a hot water cylinder. Solar panels, or collectors, are fitted to your roof. They collect heat from the sun’s radiation. The heat transfer system uses the collected heat to heat the domestic hot water. A hot water cylinder stores the hot water that is heated during the day and supplies it for use later.
Is My Property Suitable?
Preferably you will need 2-4m2 of Southeast to Southwest facing roof receiving direct sunlight for the main part of the day. You’ll also need space to locate an additional or larger hot water cylinder, if required.
It may be necessary to gain planning permission to allow you to fit a Solar system, especially in conservation areas or on listed buildings. Always check with your Planning Department before you have a system installed.
Cost and Maintenance
The typical installation cost for a domestic flat plate collector system is £2,000 – £3,000. or an Evacuated tube systems will cost £3,500 – £4,500.
You can fit or build the system yourself. But although it may be cheaper it will take longer and you’ll need a certain level of skill. Note however that DIY jobs are not normally eligible for grant funding.
A Solar hot water systems generally come with a 10-year warranty and require very little maintenance. A yearly check by the householder and a more detailed check by a professional installer every 3-5 years should be sufficient. Your supplier will give you exact maintenance requirements.
Solar PV
You can use PV systems for a building with a roof or wall that faces within 90 degrees of south, as long as no other buildings or large trees overshadow it. If the roof surface is in shadow for parts of the day the output of the system decreases.
Solar panels are not light and the roof must be strong enough to take their weight, especially if the panel is placed on top of existing tiles.
Solar PV installations should always be carried out by a trained and experienced installer.
By producing your own electricity you essentially become a supplier yourself. As well as producing electricity for your own needs, there will be times when your system produces more than you need. In this situation, the surplus electricity will be fed into the local network.
It is the responsibility of your chosen installer to ensure your system is installed according to the existing electrical installation regulations. It is also their responsibility to contact the local Distribution Network Operator to advise that a new PV system is being connected in their area.
The connection of PV systems to the electricity grid has become standard procedure and paperwork will likely be dealt with by the installer as part of the service.
Cost and Maintenance
Prices for PV systems vary, depending on the size of the system to be installed, type of PV cell used and the nature of the actual building on which the PV is mounted.
For the average domestic system, costs can be around £4,000- £9,000 per kWp installed, with most domestic systems usually requiring between 1.5 and 2 kWp.
A further option is solar tiles which cost more than conventional panels and also panels that are integrated into a roof are more expensive than those that sit on top.
Planning Considerations
It may be necessary to gain planning permission to allow you to fit a PV system, especially in
conservation areas or on listed buildings. Always check with your Planning Department before you have a system installed
Funding
For Solar PV systems there is grant maximum of £3,000 per kWp installed, up to a maximum of £15,000 subject to an overall 50% limit of the installed cost (exclusive of VAT)
Please note that prior to issue of any grant towards renewables, the BERR will ensure the applicants property has already been made efficient in its energy use. Small Scale Wind Power and Your Home
Wind speed increases with height so it’s best to have the turbine high on a mast or small tower and generally speaking the ideal site is a smooth hill top hill with a flat, clear exposure, free from excessive turbulence and obstructions such as large trees, houses or other buildings.
However, small-scale building-integrated wind turbines suitable for urban locations have now been developed e.g. ‘Windsave’ and can be sited near to the apex of the roof – similar to an aerial or satellite dish.
Knowledge of the local wind is critical to designing a wind energy system and predicting output. For domestic installations a good source of information on local wind speeds is the NOABL database which can be accessed from the British Wind Energy Association website.
Planning issues such as visual impact, noise and conservation issues also have to be considered.
Please contact info@1staction.com for installation information
Grid-Connected System?
Small scale wind systems can installed where there is a grid connection. A special inverter and controller convert DC electricity to AC at a quality and standard acceptable to the grid. No battery storage is required. Any unused or excess electricity can be exported to the grid and sold to the local electricity supply company.
By producing your own electricity you essentially become a supplier yourself. As well as producing electricity for your own needs, there will be times when your system produces more than you need. It is your installer’s responsibility to contact the local Distribution Network Operator to advise that a new wind energy system is being connected in their area.
The connection of wind energy systems to the electricity grid has become standard procedure and paperwork will likely be dealt with by the installer as part of the service.
Cost and Maintenance
Systems up to 1kW will cost around £3000 whereas larger systems in the region of 1.5kW to 6kW would cost between £4,000 – £18,000 installed. These costs are inclusive of the turbine, mast, inverters, battery storage (if required) and installation, however it’s important to remember that costs always vary depending on location and the size and type of system.
Turbines can have a life of up to 20 years but require service checks every few years to ensure they work efficiently. For battery storage systems, typical battery life is around 6-10years, depending on the type, so batteries may have to be replaced at some point in the system’s life.
Funding
Grant maximum £1,000 per kW installed, up to a maximum of £5,000 subject to an overall 30% limit of the installed cost (exclusive of VAT)
Please note, that prior to issue of any grant towards renewables, the BERR will ensure the applicants property have already been made efficient in its energy use.
Ground Source Heat Pumps
Benefits
The efficiency of a ground source heat pump system is measured by the coefficient of performance (CoP). This is the ratio of units of heat output for each unit of electricity used to drive the compressor and pump for the ground loop. Average CoP over the year, known as seasonal efficiency, is around 3-4 although some systems may produce a greater rate of efficiency. This means that for every unit of electricity used to pump the heat, 3-4 units of heat are produced, making it an efficient way of heating a building. If grid electricity is used for the compressor and pump, then you should consult a range of energy suppliers to benefit from the lowest running costs, for example by choosing an economy 10 or economy 7 tariff.
How It Works
There are three important elements to a ground source heat pump:
Ground Loop
This is comprised of lengths of pipe buried in the ground, either in a borehole or a horizontal trench. The pipe is usually a closed circuit and is filled with a mixture of water and antifreeze, which is pumped around the pipe absorbing heat from the ground. The ground loop can be:
Vertical, for use in boreholes, Horizontal, for use in trenches or a Spiral coil also for use in trenches
Heat Pump
In the same way that your fridge uses refrigerant to extract heat from the inside, keeping your food cool, a ground source heat pump extracts heat from the ground, and uses it to heat your home.
A ground source heat pump has three main parts: 1) The evaporator, (e.g. the coiled element in the cold part of your fridge) absorbs the heat using the liquid in the ground loop; 2) The compressor, (this is what makes the noise in a fridge) moves the refrigerant round the heat
pump and compresses the gaseous refrigerant to the temperature needed for the heat
distribution circuit and 3) The condenser, (the hot part at the back of your fridge) gives up heat to a hot water tank which feeds the distribution system.
Heat Distribution System
This consists of under floor heating or radiators for space heating and in some cases water storage for hot water supply.
Ground Source Heat Pumps and Your Home
You should consider the following issues if you’re thinking about installing a ground source heat pump. An accredited installer will be able to provide more detailed advice.
You will need space outside your house for the ground loop.
The ground will need to be suitable for digging a trench or borehole.
What fuel is being replaced? If it’s electricity, oil, LPG or coal the savings will be more favourable than gas. Heat pumps are a particularly good option where gas is unavailable.
The type of heat distribution system. Ground source heat pumps can be combined with radiators but these will normally be larger than with standard boiler systems. Under floor heating is better as it works at a lower temperature.
Please contact info@1staction.com fo urther information
Costs
A typical 8 – 12kW system costs £6,000 – £12,000 (not including the price of distribution system). This can vary with property, system size and location. Vertical ground loop systems are significantly more expensive to install than horizontal ground loops, due to the higher cost of drilling a borehole. When installed in an electrically heated home a ground source heat pump could save as much as £1000 a year on heating bills and almost 7 tonnes of carbon dioxide a year. Savings will vary depending on what fuel is being replaced
Funding
For Ground Source Heat Pump systems there is a maximum £1,200 grant, subject to an overall 30% limit (exclusive of VAT).
So why aren’t we queuing to install these systems?
It has to be the issue of installation costs against the savings we could make.
In the long term there will be savings but in a society who changes their homes on average every seven years we cannot expect to get a return on our investment in that time and we don’t really get the added value of the cost of the investment when we sell.
There are grants and loans available to encourage us but not sufficient to make the difference.
The other trouble is that much of the technology is still developing and in this technological world we have come to believe that technology gets cheaper as it develops. We can buy a 42” plasma television now for 25% of the price we would have paid two years ago.
The two systems that are now well tried are the Solar water heating systems that works alongside your conventional water heater costing between £2,000 to £4,500 and Ground Source Heat Pumps which can cost between £6,000 – £12,000
It’s a choice we all can make now and a choice we will no doubt all have to make in the future if we want to keep this wonderful planet that we share.