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Low carbon heating jargon buster – from CoP to SEG

Interested in making your home more eco-friendly but getting tripped up by all the low carbon lingo? We're here to help.

This jargon buster will break down the key terms you'll hear, making heat pump technology and solar panels easy to understand. From explaining the key parts of a heat pump to SEG, we've got you covered.


AC stands for 'alternating current' whereas DC stands for 'direct current'. The photovoltaic technology found in a solar panel converts sunlight into direct current electricity but in order for this to be usable or exported to the grid, the electricity must be converted to alternating current by an inverter.



This means a large group of solar panels.



ASHP is short for air source heat pump. The technology used in an ASHP captures thermal energy from outside to be used in your home. Air source heat pumps use your electricity supply to do this. An air source heat pump can replace your traditional fossil fuel boiler or can be used alongside your boiler in a hybrid set-up. Air source heat pumps are 300 times more efficient than a standard gas boiler.


Battery storage

Battery storage allows you to maximise the potential of your renewable energy-generating tech. The excess energy you create can be stored for use at a later time. If you don't have a battery, the energy produced from your solar panels (or other renewable energy-generating tech) must be used or exported to the grid. Not only does battery storage assist in furthering your energy independence goals by becoming less reliant on your energy supplier, but it can also provide further savings on energy bills.



The Boiler Upgrade Scheme is a government grant which was created to encourage property owners in England and Wales to install low-carbon heating solutions such as air source heat pumps. If eligible for the BUS, you can receive:

  • £7,500 off the cost and installation of an air source heat pump
  • £7,500 off the cost and installation of a ground source heat pump, including water source heat pumps
  • £5,000 off the cost and installation of a biomass boiler


Carbon footprint

This is the sum of all greenhouse gas emissions, like carbon dioxide and methane, caused by human activity.



A component used in the air source heat pump system. Gas is passed through a compressor which uses electricity to increase its temperature via pressure leveraged upon it.



A component used in the air source heat pump system. When the heat from outside is transferred into the heat pump system, the condenser is the mechanism which transfers this heat from the system into your home's water system which heats your radiators.



This stands for Coefficient of Performance. This is a measure of efficiency for heat pumps. It compares the useful heating (or cooling) output of the system to the electrical energy input. A higher COP indicates a more efficient system, which translates to lower energy consumption and running costs.



Energy Saving Trust - This is a British organisation that promotes energy efficiency, energy conservation, and the sustainable use of energy to reduce carbon dioxide emissions.



Used in an air source heat pump system in the external unit. The evaporator absorbs heat energy from air blown across a heat exchanger using fans.



Export relates to taking excess energy generated in your home and diverting it to the grid. To earn money for exporting excess electricity that your renewable energy-generating tech produces, you'll need to join a Smart Export Guarantee (SEG) tariff. To join our SEG tariff, you'll need a smart meter that sends us half-hourly reads.


Feed in Tariff

In an effort to boost the uptake of renewable energy, the government previously offered a scheme called the Feed-in Tariff (FIT).



The grid relates to the connection your home has to the nationwide electricity distribution and transmission networks.


Heat Exchanger

Used in an air source heat pump system. The heat exchanger acts as a bridge, allowing the heat pump to efficiently move heat from the outside environment to your indoor space, providing warmth without directly generating heat itself.


High temperature heat pump

These heat pumps can heat water to higher temperatures than a low temperature heat pump. When operating at high temperatures, the system may use more electricity than a low temperature heat pump, but this could mean that larger radiators aren't required.



Hybrid heating systems combine traditional heat sources with renewable ones to provide heat, cooling and hot water for your home. Typically this means installing a heat pump alongside a fossil fuel boiler.



This is the component within the solar panel system which converts the direct current electricity generated by solar panels into usable alternating current electricity.



kWh is the unit of measurement used to measure energy. It stands for kilowatt hours. This measurement is based on watts (W) and a kilowatt is simply a thousand watts.


Low temperature heat pump

Low temperature heat pumps are a type of heat pump that usually heat the water in your heating system to a lower temperature than you may have experienced with an oil or gas based heating system.



MCS stands for Microgeneration Certification Scheme. As an organisation, they set and uphold standards for low-carbon technology products, installers, and their work.



An optimiser is fitted to each solar panel to optimise the power output generated by each panel.



This is short for photovoltaic which relates to the production of electricity through exposure to light.


PV diverter

A PV diverter is a device that redirects excess solar energy that your home isn't using to power an appliance, typically an immersion heater for hot water.



This is the fluid contained within the air source heat pump which absorbs the heat from the air around us.



SEG is short for Smart Export Guarantee. This is a scheme put in place by the government which replaced the Feed-In tariff. When a customer signs up for SEG they can get paid for any surplus generation from their solar PV by exporting to the grid.



In the context of energy production, solar relates to energy which is derived from the sun.

Ready to make your home more low carbon?