Glossary/FAQs
Not sure what a word means? Or how something in the energy system works? This page explains common energy terms and answers questions people often ask.
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- Energy Fundamentals
- Energy Soruces
- The Electricity System
- Energy Storage and Supply
- The Energy Transition
- Technology and Innovation
- FAQs
Energy Fundamentals
Watt (W)
A unit that measures how much power something uses at one moment. Your phone charger might use 10W; a kettle uses 2,000W.
Power
How fast energy is being used or transferred. Measured in watts or kilowatts.
Kilowatt-hour (kWh)
A unit that measures how much energy is used over time, such as how much electricity a home uses in a day.
Energy
The ability to do work — from moving objects to powering devices. Everything you do needs energy.
Electricity
A form of energy that travels through wires and powers lights, phones, computers and appliances.
Energy Soruces
Wind power
Electricity made when wind spins turbine blades connected to a generator.
Solar energy
Energy from the sun that solar panels turn into electricity.
Renewable energy
Energy from sources that won't run out, such as wind, sunlight and flowing water.
Nuclear power
Energy released by splitting uranium atoms. Produces no CO₂ but generates radioactive waste.
Hydropower
Electricity generated by water flowing through dams or rivers.
Geothermal energy
Heat energy from inside the Earth, used for heating or to generate electricity.
Fossil fuel
Coal, oil and gas formed from ancient plants and animals. Burning them releases energy and greenhouse gases.
Biomass
Energy from organic matter, wood, crop waste, food scraps, that can be burned for heat or converted to fuel.
The Electricity System
Transmission
Moving electricity from power stations to local networks across long distances at high voltage.
Transformer
A device that changes the voltage of electricity. High voltage is used to move electricity long distances, and lower voltage is used safely in homes and schools.
Substation
A place where electricity is controlled, redirected and prepared for the next part of its journey.
Smart grid
An electricity network using digital technology and sensors to balance supply and demand in real time.
Grid (National Grid)
A large network of power lines, cables and equipment that moves electricity across the UK.
Demand response
Using smart systems to shift when people use electricity (e.g., charging electric cars at night when demand is low).
Energy Storage and Supply
Pumped hydro storage
A way of storing energy by pumping water uphill and releasing it later to generate electricity again.
Hydrogen
A fuel produced from water or natural gas that can be used to generate electricity or heat.
Energy storage
Technology that captures excess renewable energy for later use when demand is high or weather changes.
Battery storage
A way of saving electricity so it can be used later, from small batteries to very large ones connected to the grid.
The Energy Transition
Net zero
Emitting no more greenhouse gases than you remove. Global target: reach this by 2050.
Energy efficiency
Using less energy to do the same job. LED bulbs use 75% less energy than old incandescent ones.
Emissions
Gases released when fuels are burned. Some emissions, like carbon dioxide, contribute to climate change.
Decarbonisation
Reducing or eliminating carbon emissions from energy, transport, industry and buildings.
CCUS (Carbon Capture, Utilisation and Storage)
Technology that captures CO₂ from the air or industrial processes and stores it, preventing it from entering the atmosphere.
Carbon footprint
Total greenhouse gases produced by your activities. Measured in tonnes of CO₂ equivalent.
Technology and Innovation
Smart home technology
Internet-connected gadgets, like smart speakers and thermostats, that learn your habits and automatically turn things on and off to save energy.
Heat pump
Technology that moves heat from outside air to warm homes. Three to four times more efficient than gas boilers.
Electrification
Replacing fossil fuel systems (gas heating, petrol cars) with electric alternatives powered by clean energy.
Electric vehicle (EV)
Car powered by a rechargeable battery instead of petrol or diesel.
FAQs
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Will AI replace energy jobs?
AI will change jobs, not eliminate them. Energy systems need engineers, technicians and humans making decisions. AI handles routine forecasting and maintenance — freeing people for more strategic work.
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What qualifications do I need?
It depends on the role. Some apprenticeships don't require A-levels. Others need degrees. Physics and maths GCSEs keep options open. Check our career tool for entry requirements for 40+ specific roles.
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Do I need to be good at maths to work in energy?
Maths helps, especially for engineering and data roles. But energy careers span creative, technical, business and practical skills. There's something for everyone.
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What jobs exist in renewable energy?
Hundreds. Engineers design systems, technicians maintain them, data scientists optimise grids, electricians install infrastructure. Plus sales, project management and policy roles. Check "Find Your Energy Career" for specific paths.
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What is net zero and why 2050?
Net zero = emitting zero more CO₂ than you remove. 2050 is the target because climate models show we need to stop new emissions by then to limit warming. Waiting longer makes it harder and more expensive.
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Why do we need to change how we get energy?
Burning fossil fuels releases CO₂, which causes climate change. Renewables like wind and solar don't. We're also running out of fossil fuels, so renewables are more sustainable long-term.
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How can I reduce my energy use?
Turn off devices on standby, use natural light, wear a jumper instead of heating your room, unplug chargers. Households that do these save 10–15% on energy bills.
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Does my energy use actually matter?
Yes. Your home's heating/cooling and devices account for about 25% of UK emissions. Streaming, gaming and phone charging add up. Small changes make a difference.
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When I flip a switch, why does the power come instantly?
The system is already live. Flipping the switch completes a circuit, letting electricity flow straight to your device.
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Why do we need energy storage?
Because we don't always use energy at the moment it's produced. Storage helps save electricity for later, especially when demand is high or the weather changes.
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What happens when lots of people use electricity at the same time?
The system adjusts in real time. Power stations increase output or stored energy is released to keep everything running smoothly.
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Why can't we just make all energy locally?
Different energy sources need different conditions — wind, water, fuel or space. The grid connects these places so electricity can reach everyone reliably.
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How does the grid send electricity where it's needed?
Automatically. The grid constantly balances supply and demand, sending more electricity to places using more power, a bit like water flowing through pipes.
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Why does electricity lose energy as it travels?
Some energy escapes as heat when electricity moves through wires. Using high voltage helps reduce these losses, which is why transformers are important.
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What's the difference between energy and electricity?
Energy is the bigger idea — it's anything that can cause change or do work. Electricity is one type of energy that flows through wires and powers everyday devices.
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What is a My Energy Future Champion?
A mix of renewables is more resilient than relying on one.
Different energy sources work in different conditions:
- Wind is powerful in coastal areas.
- Solar works anywhere with daylight.
- Geothermal is reliable in specific regions.
- Hydro needs water.
- Biofuels power transport and aviation where electricity isn’t practical yet.
Let’s shape the future together
Backed by industry, My Energy Future is brought to you by OPITO and partners to build a safe, skilled workforce.