Jargon Busting: Your Energy Industry Glossary

By Guste Nov 02, 2021

With the eyes of the world on COP26 – the most important climate change summit of our time – the event is all over the news. Don’t worry if you get a bit confused with the terminology: we thought of creating this handy guide to explain some of the energy jargon.

What is a kWh vs an MWh?

The abbreviation “kWh” stands for kilowatt-hours, which is a one-kilowatt amount of power delivered in one hour (this is what you see on your energy bill). 1 kWh = 0.001 MWh. The abbreviation “MWh” stands for megawatt-hours, which is one million watts amount of power delivered in one hour (1 MWh = 1000 kWh).


This refers to the process of reducing greenhouse gas emissions produced as a result of various energy-related sectors, such as transport, residential, commercial and industrial. Greenhouse gases is one of the main contributing factors accelerating climate change.

Carbon Footprint

Your carbon footprint is the amount of carbon dioxide which is released into the atmosphere as a result of your activities. Carbon footprint is usually expressed in the equivalent tonnes of carbon dioxide (CO2). For example, an economy class, direct, return flight from London to New York is the equivalent of 0.96 tonnes of CO2. You can calculate your own carbon footprint here or learn how to reduce your carbon footprint on our blog post here.

Time-of-Use Tariff

A time-of-use tariff is an electricity tariff where energy suppliers offer different prices at different times of the day. The price differences correspond to changes in demand for electricity, referred to as peak (generally 4-7pm, when more people are using electricity) or off-peak periods.

Time-of-use tariffs can be static, with set peak and off-peak slots each day; or dynamic, with prices varying up to every half-hour. More details on time-of-use tariffs can be found in our blog.

Flexibility services

Ofgem has defined flexibility as “modifying generation and/or consumption patterns in reaction to an external signal… to provide a service within the energy system”. Flexibility services converge three trends: demand-side response (rewarding consumers for how and when they use electricity), energy storage (using batteries to store surplus energy) and distributed generation (using low-carbon electricity generated locally).

Read more about why flexibility is the foundation of our energy future.

VPP (Virtual Power Plant)

A network of decentralised power-generating units, such as solar-power or battery-backed homes, wind farms and solar parks and flexible power consumers and batteries. It’s a type of smart grid that delivers surplus energy back into the grid to power other locations.

DNO (Distribution Network Operator)

This is a company that is responsible for distributing electricity from the national transmission grid to your home or business and maintaining the cables, equipment and substations. If you have a power cut at home, for example, you will need to call one of the six Distribution Network Operators that operate across Great Britain, depending on which one is looking after your area.

DSO (Distribution System Operator)

A new-generation DNO that takes a more active role in managing local electricity generation and use. When the transition from DNO to DSO happens, the DSO will act as a smart platform that enables a whole range of new energy technologies, such as renewable sources, energy storage and sharing and micro-grids.

MCS Accredited

This is an accreditation for installers that shows that they hold a nationally recognised quality assurance certificate which is required to be eligible for FIT payments.

Home Insulation & Energy Systems Scheme (HIES)

HIES is a consumer protection organisation covering the installation of renewable energy products. At Moixa we are HIES members and follow their stringent set of rules when dealing with our customers. 

Renewable Energy Association (REA)

A not-for-profit trade association representing British renewable energy producers that promotes the use of renewable energy in the UK.

Renewable Energy Consumer Code (RECC)

A scheme set up by the Renewable Energy Association (REA) to guarantee a high quality experience for consumers wishing to buy or lease small-scale energy generation systems for their homes.

Energy aggregation

A method for communities to combine their buying power to bargain the best energy price and use one supplier for the entire group.

Energy arbitrage

This refers to the practice of purchasing energy at a particular time and place to benefit from a lower price, storing the energy during off-peak times and then selling it when demand is high for a much higher price.

Behind-the-meter (BTM)

This is an energy storage solution that allows large businesses and whole industries to install battery storage systems on-site (i.e., behind-the-meter) to lower their energy bills. That’s achieved by using batteries to store power in off-peak times and using it when the electricity is more expensive.


Another energy storage solution that utility companies use to even out their loads. It’s a win-win method that protects the consumer from price hikes and helps the supplier avoid price drops in the wholesale market.