Perfect Green Group’s three operating divisions each bring a different blend of expertise, technologies, services and people to the table. Each one is designed to form a sustainable standalone business in its own right. They also work together, broadening the group’s total expertise and coverage of the green technology spectrum.
Perfect Green Heating
Perfect Green Heating concentrates on all things heating, such as biomass, air and ground source heat pumps. Given our background in the heating, ventilation and air conditioning markets we know the best way to engineer heating systems. We also offer support and advice on the best way to integrate renewable heating technologies into your new or existing buildings, providing description of operation, schematics and specifications.
Ground Source Heat Pump Systems (GSHP)
Air Source Heat Pump Systems (ASHP)
We can also engineer and deliver air source (ASHP) systems that absorb heat from the outside air to heat your building and its hot water, to be installed inside or outside the building. These are cheaper to install than GSHP and have similar peak specific efficiency to GSHP but less constant outputs because of the changes in ambient air temperature. Read more
Perfect Green Solar
Perfect Green Solar will engineer a photovoltaic system that delivers your energy efficiency savings at a cost acceptable to you or your client. We are experts in utilising the latest design software including PV Sol and PVGIS AutoCAD, and we monitor technology and legislation changes daily to provide the best possible up to date advice. PGS work hard to keep our customers updated and informed. We also work with PGH in providing solar thermal solutions that can be integrated into the heating system directly or help support a ground source heating application.
Perfect Green Power
Perfect Green Power focuses on wind and combined heat and power (CHP) technologies. We deliver both these technologies by working closely with established and experienced third parties. PGP don’t build wind turbines or CHP plant but we have experts at our disposal to apply them.
Combined Heat and Power
Increasing legislation and the need to reduce emissions means there is a growing need for decentralised generation technologies that can cut carbon and reduce climate change. By optimising the use of either fossil or renewable fuels our Combined Heat and Power systems (CHP) provide a highly effective way of reducing carbon emissions and lowering your energy costs.
Ground source heat pump
Ground source heat pump (GSHP) systems take heat from the ground (mainly solar energy that’s been absorbed) using a borehole or a series of pipes under the building and use it to heat radiators, other heating systems and hot water.
How it works
The ground around your building works like a natural solar thermal panel, absorbing heat from the sun. Much of this heat remains trapped in the ground. A modest heat differential, only a few degrees, multiplied over a large surface area adds up to a high amount of energy that can be tapped.
The installation flows fluid in a ‘ground loop’ pipes through the ground (or down into a borehole and up again if space is limited). The ground loop flow passes through a heat pump, which uses a heat exchanger to extract the thermal energy. This is then used to heat the building’s hot water and central heating systems
For more information see the Energy Saving Trust’s GSHP page.
- Heats both your building and hot water.
- Is 200-300 per cent more efficient than a standard boiler.
- Will not be affected by the seasons because a few metres down, the ground is protected from extremes of temperature and is almost constantly around 10 degrees Celsius.
- GSHP systems over 45kW and up to 350kW thermal attract 5.5p/kwhr RHI for a period of 20 years.
- Horizontal ground loop systems are cheaper but need plenty of ground space. This space must be protected from digging or disturbance.
- Where space is limited, a vertical closed loop array system running down into a deep borehole will also work but is best installed before any building work takes place.
- Heat pumps deliver lower temperatures than gas or oil fired boilers (but over much longer periods). During the winter they may need to be on constantly to heat the building.
- Radiators will tend to feel warm rather than hot to the touch. This means that GSHP systems work best on large radiators or under floor systems in a well-insulated building.
Calculate your potential GSHP savings here
Air Source Heat Pump Systems
What are Air Source Heat Pumps?
Have you ever felt the back of a fridge? It feels warm. In comparison, the inside of the fridge is cold – however cool the air may be, it is warmer than absolute zero; the refrigeration unit is extracting the difference in temperature.
Air source heat pumps (ASHP) work in a similar way. Heat from the air gets absorbed at a low temperature into a fluid and passed through a compressor where the temperature is increased, consequently being routed to heating systems and water circuits, or even a warm air fan.
What components make up an air source heat pump?
An outdoor heat exchanger coil: This coil extracts heat from ambient air; a rather crucial part of the technology!
An indoor heat exchanger serves to transfer the extracted heat into a medium (air or water), to be utilised by various applications such as fan coils, underfloor heating, radiators and water tanks.
Air source heat pumps are used for interior space heating and also cooling, even in colder climates. In milder climates the pumps can also be used for heating water.
Some ASHP’s have the advantage of being able to produce heat during the winter, whilst also being able to provide cooling during the summer – though it is not technically an air conditioning unit without the option to adjust the humidity of the cool air
Air source heat pumps can be used for fairly low cost space heating; a pump performing with high efficiency can provide up to four times the heat of an electric heater.
Solar Thermal systems (SHW) use heat energy from the sun to heat water for your home. A solar thermal system, like a solar PV system is most efficient when it is orientated towards south and tilted to a 30-40% angle but can still produce a high percentage of required hot water when fitted directed east or west.
How it works:
When the sun hits the panel is starts to heat the thermal transfer fluid contained within the panel, when the liquid is at the required temperature a pump station circulates it around a coil at the bottom of a tank (cylinder) full of water, heating the water within it. There are times when a solar thermal system will not heat the water to the required temperature, at this point a conventional or other form of renewable( like a heat pump) heating system will take over.
There are two main types of solar thermal technology, Flat-plates and Evacuated Tubes.
- Flat Plates are the most commonly installed SHW technology. They consist of a dark flat-plate which absorbs the solar energy. The flat plate comprises of a transparent cover (that allows solar energy to pass through but reduces heat looses), glycol and insulated backing. Though lower in efficiency, if you are looking for a an aesthetically pleasing appearance, similar to a sky-light window, this is the option for you.
- Evacuated Tubes consist of multiple evacuated glass tubes, a transparent cover and glycol. Different to the flat plates a vacuum within the tubes reduces the convection and conduction of heat loss from around the outside of the panel, therefore achieving high efficiencies, particularly in colder conditions.
See also the Energy Saving Trust’s solar water heating page.
- Solar Thermal systems are largely ‘fit and forget’ technologies with a long service life. Very little maintenance is required.
- During summer months a Solar thermal system, when sized correctly can provide all of the hot water requirements for a residential dwelling
- The government offer a premium payment incentive to customer who chose to install a solar thermal system and this qualifies for the renewable heat incentive (RHI)
- Solar thermal systems only generate hot water
- During the winter, solar thermal systems will make little contribution, a conventional heating system or renewable heat pump will be needed to heat water to the require temperature
Calculate your potential solar thermal savings here
Photovoltaic (PV) panels convert sun radiation into electricity. A PV solar system orientated towards south at 30-40 Degrees above the horizon will give the most optimum electricity generation but will still generate a good amount of electricity even if fitted facing due East or West.
How it works:
Solar PV panels consist of many photovoltaic cells. Each cell is made from layers of semi-conducting material, usually silicon.
There are 4 main types of solar PV modules on the market and they range in efficiency.
- Polycrystalline (sometimes known as multicrystalline) are the most popular technology used in the UK. They have a distinctive appearance which looks like shattered glass or mosaic because each cell within the panel is comprised of a block of multiple crystals rather than just one single silicone crystal. These offer an efficiency rating of 13-16%
- Monocrystalline was the first generation of solar technology and it has been used since the 1950’s. The monocrystalline modules have a typically black or iridescent blue appearance and use a single silicone crystal. Although slightly more expensive than a polycrystalline module they offer between 14-20% efficiencies, enabling homes and businesses to generate a comparable amount of electricity even if the building/ground space is limited.
- Thin-Film (Amorphous) Initially used in hand-held calculators but now available in much larger modules used in large integrated building installations, Thin-film is available as a standard ‘panel’ but as this can also be deposited onto glass, plastic or metal thin-film is available as a flexible fabric. Efficiencies range from 12-20%.
- Hybrid HIT (Heterojunction Incorporating Thin-Film) incorporates two types of photovoltaic cells within one panel, by placing one material into contact with another the efficiencies are greater than a single type of crystalline. These premium solar modules offer efficiencies of 17-19%.
PV systems can be retro-fitted onto existing structures, during the build of a new property or renovation and even ground-mounted on a frame.
You can find out more on the Energy Saving Trust’s solar electricity page.
Calculate your potential solar PV savings here
- Solar panel efficiencies reduce very slowly, your solar panels can generate electricity over 40 years
- PV panels have no moving parts to require very little maintenance over their life span
- Solar Panels are unobtrusive and can be designed to have little to no impact on the surrounding landscape
- There are great Feed in-tariff’s which are available from the government which offer guaranteed income over 20 years
- Solar panel generation is very affected by shading from tree’s and other buildings and may not always be a suitable technology
- Electric output’s from the panels can fluctuate, generating large amounts of energy during a sunny day and none at all at night
- If the system connected to the grid the electricity generated must be used when it’s been made
- In order to use the electricity at another time battery storage must be supplied which is an additional cost.