Glossary

Air and ground source heat pumps

The air source heat pump absorbs heat from the outside air into a liquid refrigerant at a low temperature. Using electricity, the pump compresses the liquid to increase its temperature. It then condenses back into a liquid to release its stored heat. Heat is sent to your radiators or underfloor heating.

A ground source heat pump transfers heat from the ground into buildings. Radiation from the sun heats the earth. The earth then stores the heat and maintains, just two metres or so down, a temperature of around 10°C even throughout the winter.

Biomass boiler

To talk about biomass boilers, we should first clarify what ‘Biomass’ means. ‘Biomass’ is fuel that is obtained from organic matter, the most widely used is wood. So, a biomass boiler is a heating system that uses natural/non-fossil fuel resources to create heat for use throughout your home or premises.  

Cavity wall insulation 

Many cavity walls can be insulated by injecting insulation material into the cavity from the outside. A specialist company will drill holes in the outside walls, inject insulation through the holes and then seal them with cement. The insulation material is usually either mineral wool or polystyrene beads, but polyurethane foam may sometimes be used instead.

Condensing boiler

A condensing boiler uses condensing technology to make better use of the heat it generates. When a fuel such as gas or oil is burned, gases are released via a flue. In a non-condensing boiler system these gases would be released into the atmosphere and their heating potential would be lost. Condensing boilers are far more efficient than non-condensing boilers, with newer models able to reach over 90% efficiency. Non-condensing boilers are only able to achieve between 70-80% efficiency.

Condensing boilers

Condensing boilers are water heaters fueled by gas or oil. They achieve high efficiency (typically greater than 90% on the higher heating value) by condensing water vapour in the exhaust gases and so recovering its latent heat of vaporisation, which would otherwise have been wasted.

Cylinder thermostat

Cylinder thermostats control and regulate the temperature of water inside a hot water cylinder. They measure the temperature of the stored water and if it falls below a certain threshold, they will send a signal to heat the water up again.

Double glazed windows

Double glazing uses two panes of glass separated by a layer of argon gas to keep your home more energy efficient and reduce sound. The argon gas is a poor heat conductor and therefore keeps warm air from escaping, while the second pane of glass acts as a barrier to noise.

Draught proofing

Draught proofing (or draught exclusion) is one of the cheapest and easiest ways to cut energy costs in the home, whether you live in a house or a flat. The concept is really simple: stop cold air coming in and prevent warm air from escaping, using things like draught excluders.

EPC

A certification giving a property an energy efficiency rating from A (high) to G (low) by looking at various factors (eg age, type, construction, insulation, heating systems) to promote the improvement of the energy performance of buildings and identify ways to improve energy performance and reduce associated costs.

External or internal wall Insulation

External wall solutions comprise of an insulation layer fixed to the existing wall, with a protective render or decorative finish. Dry cladding offers a wide range of finishes such as timber panels, stone or clay tiles, brick slips or aluminium panels.

Internal wall insulation involves the application of insulation to the interior face of external walls in order to improve the thermal performance of the property. There are four main methods of installation — the most common (but not always the most effective) is building a new stud wall, to which insulation can be added.

Flat roof insulation

Flat roof insulation is used to enable a room to feel warmer in the winter and cooler in the summer months. Wood fibre, cellular glass and polystyrene (EPS or XPS) all have good insulation properties, but foam works particularly well and is often found in modern constructions.

Floor insulation

Insulating a floor means adding an insulating material beneath the floorboards or above solid floors, reducing heat escaping through the floor into the ground. Insulation also acts to prevent draughts coming up through the floorboards.

Flue gas heat recovery

The unit is connected directly to the flue. It’s a heat exchanger which extracts residual energy from the flue gases exiting from the boiler. This energy is then used to pre-warm the water that is fed into the combi boiler reducing the amount of gas required to reach the desired hot water temperature.

Heating controls

Heating controls for  heating system consist of roomstats, programmers and thermostatic radiator valves (TRV’s). All help regulate temperature reducing the cost of heating. 

Hot water cylinder insulation

Having good insulation on your hot water cylinder means your water stays hot and you don’t waste money heating it up twice. Some cylinders can be covered in rigid foam, others will need a ‘tank jacket’ fitted. Insulation jackets can be bought in most good DIY stores and can easily be fitted by yourself to keep costs down.

Insulated doors

By installing insulated doors, you can cut down on drafts and reduce noise.

Loft insulation

Loft insulation is a barrier of material in your roof space that traps heat. It can either be laid between the joists (the horizontal beams along the floor of your attic) or the rafters (the angled beams that support the roof). Either way, it’s like a big cosy blanket that slows down the transfer of heat between your living space and the outside world. Insulation not only warms your home in winter, but keeps it cool in summer. 

Low energy lights

Replacing light bulbs with energy efficient can save up to 80% and are an easy simple change.

Micro-CHP

Combined Heat & Power (CHP) can be used to generate electric and heat by burning biomass or fossil fuel.

New or replacement boiler

Just like technology the older a boiler the less efficient it is. Newer heating systems have new technology and generally save money and are more efficient.

New warm air unit

Just like technology the older the warm air unit is the less efficient – newer heating systems have new technology, generally save money and are more efficient.

Roof room insulation

Installing room in roof insulation involves insulation boarding being fitted in between the rafters underneath the existing plasterboard walls. Room in roof insulation works by trapping heat within your home to create a blanket effect. This allows you to more easily maintain a warm home without using as much energy to do so, saving you money on your energy bills.

Secondary glazing

Secondary glazing involves installing another glass layer behind an existing single glazed window. While secondary glazing can help reduce heating costs it is still not as efficient as double or triple glazing.

Solar photovoltaic panels

Solar panels produce electricity by converting sunlight into a direct current (DC) which passes into an inverter. The inverter converts this DC electricity into usable electricity for your home or commercial building. Solar PV panels offer a number of advantages beyond solar water heating. Due to their simpler design – solar photovoltaic panels have no moving parts – they need little long-term maintenance.

Solar water heating

Solar water heating systems, or solar thermal systems, use free heat from the sun to warm water. Solar water heating systems capture heat from sunlight via a solar thermal collector – a low-profile box with a similar appearance to a solar photovoltaic panel that sits on your building’s roof, or in an open area that receives ample sunlight.

Storage heaters

Storage heaters are a type of electric heater, usually found in homes that don’t have a gas supply. They’re designed to work with a 2 rate tariff, to make use of cheaper, overnight electricity rates. Overnight they absorb and store up energy – typically in ceramic or clay bricks inside the heater. This energy can then be used to heat your home the following day. 

Waste water heat recovery system

WWHR extracts heat from the water when you use your shower and repurposes it to warm the incoming mains water. WWHR can be connected to showers and showers over baths. It does this by passing your waste water through a heat exchanger and then using it to pre-warm the cold feed of your thermostatic shower.

Wind turbine

A domestic, or home wind turbine, is a device that can turn wind energy into clean electricity for your home. It’s like a miniature version of the much bigger wind turbines you’ve likely seen around the UK, in fields, or just off the coast. The basic science is the same, but home wind turbines are more compact.