Frequently Asked Questions

Please read our FAQ and if any of your questions are not answered feel free to contact us.

What is a Heat Pump and how does it work?

A heat pump is an electrical device that extracts heat from one place and transfers it to another. The heat pump is not a new technology; it has been used in Canada and around the world for decades. Refrigerators and air conditioners are both common examples of this technology.

Heat pumps transfer heat by circulating a substance called a refrigerant through a cycle of evaporation and condensation. A compressor pumps the refrigerant between two heat exchanger coils. In one coil, the refrigerant is evaporated at low pressure and absorbs heat from its surroundings. The refrigerant is then compressed en route to the other coil, where it condenses at high pressure. At this point, it releases the heat it absorbed earlier in the cycle.

Refrigerators and air conditioners are both examples of heat pumps operating only in the cooling mode. A refrigerator is essentially an insulated box with a heat pump system connected to it. The evaporator coil is located inside the box, usually in the freezer compartment. Heat is absorbed from this location and transferred outside, usually behind or underneath the unit where the condenser coil is located. Similarly, an air conditioner transfers heat from inside a house to the outdoors.

The heat pump cycle is fully reversible, and heat pumps can provide year-round climate control inside your home – heating in winter and cooling/dehumidifying in summer. Since the ground and air outside always contains some heat, a heat pump can supply heat to a house even on cold winter days. In fact, air at -18°C contains about 85 percent of the heat it contained at 21°C.

What is Photovoltaic Solar?

solar panel works by allowing photons, or particles of light, to knock electrons free from atoms, generating a flow of electricity. Solar panels actually comprise many, smaller units called photovoltaic cells. (Photovoltaic simply means they convert sunlight into electricity.) Many cells linked together make up a solar panel.

Solar panel modules and solar PV systems are usually comprised of solar panels, an inverter, isolator switches, a PV generation meter and cables. Some things to think about when considering installing a solar system: The more panels you can fit on your roof, the more expensive the system will be to purchase and install, but the more electricity you will produce. The electricity produced by the PV panels is direct current (DC) before it can be used in the home, it has to be converted to safer alternating current (AC) using a box called an inverter. This is often placed in the loft. For safety, isolator switches are also placed before and after the inverter. A PV generation meter is connected inside your home, so you can see a real time display of how much electricity the system is generating. The meter also measures the amount of electricity exported to the grid, and this is used to calculate your Feed-in Tariff payment, which provides cash in return for generating your own electricity. Finally, if you want to export excess electricity to the grid, there will be another cable to your consumer unit (fuse box).

What is Heat Recovery Ventilation and how does it work?

Creating new and ultra-efficient renewable energy technologies is not just about harnessing the sun or wind and feeding it into our homes and office buildings. Making the most of what is already there also helps reduce our collective impact on the environment, and that includes the amount of heat we lose to the environment on a daily basis.

Heat recovery systems work by drawing on that potentially valuable warm air or water in a property and getting it to work just a little bit harder for us.

In a world without a green technology like heat recovery, air circulates around an office, becomes stale and is replaced by colder air that it is warmed up by the ventilation system. What happens to that already warm, stale air? It simply gets expelled into the atmosphere. Heat recovery systems don’t replace the need for a boiler or other technology to heat your radiators but it does help them work more efficiently by recycling that warm air ensuring that you get the most out of it.

For domestic premises, a recovery system could help save on energy bills and keep the house warm during the winter months. It’s easier to lose valuable heat in our homes, we simply open a window and that warm air just flies out into the atmosphere. With a ventilation system you get fresh, warm air constantly circulating through the house. For businesses and industry, heat recovery lies at the heart of making the work place and factory floor a far more efficient place.

How does it work?

heat recovery system can work via a ventilation system which is positioned at the top of the building. Rather than just draw the stale air out and replace it with new air, first of all it works to draw the heat from the outgoing air and passes it to the incoming air.

Heat recovery ventilation works independently of your normal heating system. In each room there are ventilation ducts with filters that feed the air in and out of the space, all leading to a heat exchanger that is either placed in the loft or on the roof of a building.

This heat exchanger is the brain of the heat recovery system, moving the stale air through hundreds of small pipes whilst drawing in cold air from outside in other ducts. These flow past each other without mixing physically but the heat is drawn from the stale air to the cold air, which is then fed back down into the pipes and into the rooms. The stale air, minus its heat, is then expelled into the atmosphere.

The technology for heat recovery systems has improved dramatically over the years and there are now systems available that profess to extract up to 90% of the heat from stale air and return it to the fresh air that is circulating back into the system.

Different systems are needed to maximize the use of waste energy, converting it to something useful that can bring down costs and reduce the impact on the environment.

What are the benefits of installing Renewable technologies?

You will be:

  • making use of secure and local resources.
  • reducing your dependence on non-renewable energy.
  • helping to reduce the production of carbon dioxide and other greenhouse gases.
  • creating new jobs in renewable energy industries.
  • reducing your energy bills & in some cases you can generate income by selling your surplus energy back to your energy provider.

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Co, Donegal


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