Renewable Energy Technologies
Expert-defined terms from the Certificate in Energy Planning and Policy course at London School of Planning and Management. Free to read, free to share, paired with a professional course.
Algae Biofuel – Related terms #
microalgae, biodiesel. A fuel derived from lipid‑rich algae cultivated in photobioreactors or open ponds. Example: Producing biodiesel from *Nannochloropsis* species. Practical application includes supplementing diesel in maritime transport. Challenges: High production costs, energy‑intensive harvesting, and maintaining optimal growth conditions.
Anaerobic Digestion – Related terms #
biogas, methane. Biological process that breaks down organic material in the absence of oxygen to produce biogas (primarily methane and CO₂). Example: Farm‑scale digesters converting manure into electricity. Practical application: Combined heat and power (CHP) systems for rural communities. Challenges: Feedstock variability, odor control, and need for skilled operation.
Biomass – Related terms #
solid fuel, bioenergy. Organic material from plants or waste used as fuel for heat, electricity, or transport. Example: Wood pellets burned in residential boilers. Practical application: District heating networks in cold climates. Challenges: Sustainable sourcing, land‑use competition, and emissions from combustion.
Biomass Gasification – Related terms #
syngas, thermal conversion. Thermochemical conversion of solid biomass into a combustible gas mixture (syngas) through partial oxidation at high temperatures. Example: Gasifying agricultural residues to power a gas turbine. Practical application: Flexible generation in remote areas. Challenges: Tar formation, feedstock uniformity, and system complexity.
Biofuels – Related terms #
ethanol, biodiesel. Liquid fuels produced from biological sources, typically used for transportation. Example: Ethanol blended with gasoline for motor vehicles. Practical application: Renewable fuel mandates in national fuel standards. Challenges: Food‑vs‑fuel debate, lifecycle greenhouse‑gas accounting, and infrastructure adaptation.
Carbon Capture, Utilization, and Storage (CCUS) – Related terms #
CCS, CO₂ sequestration. Suite of technologies that capture CO₂ emissions from point sources, transport them, and store them underground or convert them into valuable products. Example: Capturing CO₂ from a coal plant and injecting it into depleted oil fields. Practical application: Extending the life of existing fossil‑fuel plants while reducing net emissions. Challenges: High capital cost, public acceptance, and long‑term monitoring.
Capacity Factor – Related terms #
utilisation rate, plant performance. Ratio of actual energy produced by a plant over a period to the maximum possible energy it could have produced at full capacity. Example: A wind farm with a 30 % capacity factor. Practical application: Financial modelling for investors. Challenges: Variability of renewable resources leads to lower capacity factors compared to conventional plants.
Combined Heat and Power (CHP) – Related terms #
cogeneration, district heating. System that simultaneously generates electricity and useful heat from a single fuel source, improving overall efficiency. Example: A natural‑gas‑fired CHP unit supplying electricity and hot water to an industrial park. Practical application: Reducing energy costs for large facilities. Challenges: Matching heat demand with electricity generation and integrating with intermittent renewables.
Distributed Generation – Related terms #
decentralised power, micro‑grids. Small‑scale electricity generation technologies located close to the point of consumption, often connected to the local distribution network. Example: Rooftop solar PV installations on residential homes. Practical application: Reducing transmission losses and enhancing grid resilience. Challenges: Coordination with utility operations, net‑metering policies, and variability management.
Electric Vehicle (EV) – Related terms #
plug‑in car, battery‑electric. Road vehicle powered by one or more electric motors using energy stored in rechargeable batteries. Example: A city bus operating on a lithium‑ion battery pack. Practical application: Decarbonising urban transport. Challenges: Charging infrastructure, battery lifespan, and grid impacts from large‑scale adoption.
Feedstock – Related terms #
raw material, input resource. The primary material used to produce energy, such as wood chips for a biomass plant or corn for ethanol. Example: Sugarcane bagasse used in a cogeneration facility. Practical application: Determining supply chain logistics for bioenergy projects. Challenges: Seasonal availability, price volatility, and sustainability certification.
Geothermal Energy – Related terms #
earth heat, geothermal gradient. Heat extracted from the Earth’s interior to generate electricity or provide direct heating. Example: A binary‑cycle plant utilizing low‑temperature geothermal fluid to drive turbines. Practical application: Supplying base‑load power in tectonically active regions. Challenges: High upfront drilling costs, resource uncertainty, and induced seismicity concerns.
Grid‑Scale Energy Storage – Related terms #
large‑capacity battery, pumped hydro. Technologies designed to store large amounts of electricity for later use, supporting grid stability and renewable integration. Example: A 100 MW lithium‑ion battery farm smoothing wind output. Practical application: Frequency regulation and peak shaving. Challenges: Cost per kWh, degradation over cycles, and site‑specific constraints.
Heat Pump – Related terms #
refrigeration cycle, HVAC. Device that transfers heat from a low‑temperature source to a higher‑temperature sink using electricity, effectively providing heating or cooling. Example: An air‑source heat pump heating a residential building. Practical application: Improving energy efficiency in temperate climates. Challenges: Performance drops in extreme cold, and reliance on electricity generation mix.
Hydrogen – Related terms #
fuel cell, green hydrogen. The most abundant element, used as an energy carrier when produced via electrolysis or reforming. Example: Hydrogen produced from renewable electricity to fuel a fuel‑cell bus. Practical application: Sector coupling between power and transport. Challenges: Low energy density, storage safety, and cost of green production pathways.
Hydrogen Fuel Cell – Related terms #
PEMFC, electrochemical conversion. Device that converts hydrogen and oxygen into electricity, heat, and water through an electrochemical reaction. Example: A fuel‑cell vehicle with a 5 kg hydrogen tank. Practical application: Zero‑emission transport for long‑range applications. Challenges: Hydrogen refueling infrastructure and catalyst cost.
Hybrid Renewable System – Related terms #
mixed technology, complementary sources. Combination of two or more renewable technologies (e.G., Solar PV plus wind) to balance generation profiles. Example: A micro‑grid pairing solar panels with a small wind turbine and battery storage. Practical application: Increasing reliability in off‑grid communities. Challenges: System design complexity and optimal control strategies.
Inverter – Related terms #
DC‑AC conversion, power electronics. Electrical device that converts direct current (DC) from sources like PV panels into alternating current (AC) for grid use. Example: A string inverter attached to a residential solar system. Practical application: Enabling PV integration into existing AC networks. Challenges: Efficiency losses, thermal management, and grid‑code compliance.
Levelized Cost of Energy (LCOE) – Related terms #
cost per MWh, economic metric. Average net present cost of electricity generation over a plant’s lifetime, expressed in $/MWh. Example: A wind farm with an LCOE of $45 /MWh. Practical application: Comparing competitiveness of different technologies. Challenges: Accurate estimation of future fuel prices, discount rates, and capacity factor assumptions.
Load Management – Related terms #
demand response, peak shaving. Strategies to influence the timing and magnitude of electricity consumption to match supply conditions. Example: Industrial users shifting processes to off‑peak hours in response to price signals. Practical application: Reducing need for peaking plants. Challenges: Consumer participation, real‑time data communication, and regulatory frameworks.
Marine Renewable Energy – Related terms #
tidal, wave power. Energy harvested from oceanic processes such as tides, currents, and surface waves. Example: A tidal barrage generating electricity from the rise and fall of sea level. Practical application: Supplying coastal communities with clean power. Challenges: Harsh marine environment, ecological impacts, and high capital costs.
Net Metering – Related terms #
feed‑in tariff, surplus export. Billing arrangement that credits solar or other renewable generators for excess electricity fed back to the grid at retail rates. Example: A homeowner receiving credit for surplus solar generation during daytime. Practical application: Encouraging distributed generation adoption. Challenges: Utility revenue loss, grid cost allocation, and policy variability.
Off‑Grid Renewable System – Related terms #
stand‑alone, isolated micro‑grid. Energy system that operates independently of the central grid, typically using solar, wind, or diesel generators with storage. Example: A solar‑PV system with battery storage powering a remote village. Practical application: Electrification of remote areas lacking grid access. Challenges: Sizing for reliability, maintenance logistics, and financing.
On‑shore Wind – Related terms #
land‑based turbine, wind farm. Wind turbines installed on land to capture kinetic energy from the wind and convert it to electricity. Example: A 50‑MW wind farm comprising 20‑meter‑diameter rotors. Practical application: Providing regional renewable power. Challenges: Land use conflicts, visual impact, and turbulence from nearby terrain.
Photovoltaic (PV) Module – Related terms #
solar panel, solar cell. Assembly of semiconductor cells that convert sunlight directly into electricity through the photovoltaic effect. Example: A 330‑W monocrystalline module installed on a commercial roof. Practical application: Widespread rooftop and utility‑scale solar installations. Challenges: Degradation over time, temperature sensitivity, and supply chain constraints.
Power Purchase Agreement (PPA) – Related terms #
contract, off‑take. Long‑term contract where a buyer agrees to purchase electricity from a renewable project at a predetermined price. Example: A corporate PPA locking in solar electricity for 15 years. Practical application: Financing renewable projects and providing price certainty. Challenges: Contract complexity, credit risk, and regulatory changes.
Renewable Energy Certificate (REC) – Related terms #
green tag, tradable credit. Market instrument representing the environmental attributes of one megawatt‑hour of renewable electricity generation. Example: A utility purchasing RECs to meet statutory renewable portfolio standards. Practical application: Enabling compliance and voluntary green procurement. Challenges: Double‑counting prevention, price volatility, and verification mechanisms.
Renewable Portfolio Standard (RPS) – Related terms #
renewable target, mandated share. Policy that requires electricity suppliers to source a specific percentage of their power from renewable sources. Example: A state imposing a 30 % RPS by 2030. Practical application: Driving investment in renewable generation. Challenges: Balancing cost impacts on consumers and ensuring reliable supply.
Solar Concentrated Power (CSP) – Related terms #
parabolic trough, solar tower. Technology that uses mirrors or lenses to concentrate sunlight onto a receiver, producing high‑temperature heat to drive a turbine. Example: A 150‑MW CSP plant with molten‑salt thermal storage. Practical application: Providing dispatchable solar electricity. Challenges: High water consumption, land use, and the need for direct normal irradiance.
Solar Photovoltaic (PV) – Related terms #
solar electricity, rooftop solar. Technology that converts sunlight directly into electricity using semiconductor materials. Example: A 5‑MW ground‑mounted PV farm with single‑axis trackers. Practical application: Scaling from residential to utility‑scale generation. Challenges: Intermittency, grid integration, and module recycling at end‑of‑life.
Solar Thermal Collector – Related terms #
flat‑plate, evacuated tube. Device that absorbs solar radiation to heat a fluid, often used for domestic hot water or space heating. Example: An evacuated‑tube collector supplying hot water to a school. Practical application: Reducing fossil‑fuel heating demand. Challenges: Performance loss in low‑sunlight conditions and need for regular maintenance.
Supply Chain Management – Related terms #
logistics, procurement. Coordination of activities involved in sourcing, transporting, and delivering renewable energy components from raw material to installation. Example: Managing the delivery of turbine blades from overseas manufacturers to a wind farm site. Practical application: Minimizing project delays and cost overruns. Challenges: Geopolitical risks, material scarcity, and quality control.
Sustainable Bioenergy – Related terms #
certified biomass, low‑carbon. Bioenergy production that meets environmental, social, and economic criteria ensuring minimal negative impacts. Example: Using sustainably harvested forest residues for combined heat and power. Practical application: Meeting corporate sustainability commitments. Challenges: Verification, land‑use change accounting, and competition with food production.
Thermal Energy Storage (TES) – Related terms #
heat storage, molten salt. Systems that store heat for later use, often by heating a material such as molten salt or water. Example: A CSP plant storing 8 hours of thermal energy in a molten‑salt tank. Practical application: Enabling solar plants to generate electricity after sunset. Challenges: Thermal losses, material degradation, and capital cost.
Transmission Line – Related terms #
high‑voltage corridor, grid expansion. Infrastructure that transports electricity over long distances from generation sites to demand centers. Example: A 500‑kV overhead line connecting a wind farm to the regional grid. Practical application: Integrating remote renewable resources into national grids. Challenges: Permitting, right‑of‑way acquisition, and transmission losses.
Variable Renewable Energy (VRE) – Related terms #
intermittent generation, wind and solar. Renewable electricity sources whose output fluctuates with weather and time of day. Example: A solar‑PV farm whose output varies with cloud cover. Practical application: Requiring flexible grid operations and storage solutions. Challenges: Forecasting accuracy, balancing supply and demand, and maintaining grid stability.
Wind Farm – Related terms #
wind park, turbine array. Collection of multiple wind turbines sited together to generate electricity on a commercial scale. Example: A 100‑MW on‑shore wind farm with 40‑meter hub‑height turbines. Practical application: Supplying bulk renewable power to the grid. Challenges: Site selection, noise concerns, and turbine reliability.
Wind Turbine – Related terms #
rotor, nacelle. Device that converts kinetic energy from wind into mechanical energy, then into electricity via a generator. Example: A 3‑MW offshore turbine with a 100‑meter rotor diameter. Practical application: Core technology for wind energy generation. Challenges: Blade fatigue, offshore installation costs, and wake effects reducing efficiency of downstream turbines.
Yield – Related terms #
energy output, performance ratio. Measure of the actual electricity produced by a renewable system relative to its theoretical maximum. Example: A PV system achieving a 0.85 Performance ratio. Practical application: Assessing project viability and monitoring operational health. Challenges: Degradation over time, shading, and inverter efficiency losses.
Zero‑Emission Vehicle (ZEV) – Related terms #
EV, fuel‑cell car. Vehicle that produces no tailpipe emissions during operation, typically powered by electricity or hydrogen. Example: A city bus operating on a hydrogen fuel‑cell system. Practical application: Meeting urban air‑quality targets. Challenges: Fueling infrastructure, total lifecycle emissions, and consumer acceptance.