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Renewable energy guides
Plain-English, sourced guides to every major source of renewable energy, the key concepts behind them, their pros and cons, and how to use renewables at home.
Renewable energy sources
Biofuels: Ethanol, Biodiesel and Renewable Diesel ExplainedWhat biofuels are, how ethanol, biodiesel and renewable diesel are made, energy per gallon, E10/E15/E85, and whether biofuels really cut emissions.Biomass Energy: Examples, How It Works and Is It Renewable?Biomass energy explained: examples of biomass, how combustion, gasification, anaerobic digestion and biofuels work, the carbon debate, and US stats.Geothermal Energy: What It Is and How Geothermal Power Plants WorkGeothermal energy explained: what it is, how dry steam, flash and binary geothermal power plants work, enhanced geothermal systems, heat pumps and US stats.Hydroelectric Power: How Hydropower Works, Types and Key FactsHydroelectric power explained: how hydropower works, impoundment vs run-of-river vs pumped storage, the largest dams, US and global stats, and trade-offs.Offshore Wind: How Offshore Wind Turbines Work and Where They Stand in 2026Offshore wind explained: fixed-bottom vs floating turbines, the largest offshore wind farms, global capacity, and the confirmed status of US projects in 2026.Renewable Energy Sources: The 6 Main Types ComparedRenewable energy sources explained: solar, wind, hydro, geothermal, biomass and ocean energy compared by share of generation, capacity factor and cost.Solar Energy: How It Works, Costs and BenefitsSolar energy explained: how solar power works, PV vs concentrating solar, US and global solar statistics, costs per watt and home solar basics.Tidal Energy and Wave Power: How Ocean Energy WorksTidal energy and wave power explained: barrages, tidal stream turbines, lagoons, wave devices, La Rance, Sihwa and MeyGen, and why ocean energy is small.Wind Energy: How Wind Turbines Work and What They ProduceWind energy explained: how wind turbines work, turbine parts, the wind power formula, onshore vs offshore wind, and current US and global wind power statistics.
Key concepts
Clean Energy: What It Is, Types and How It Differs from Green EnergyClean energy explained: what counts as clean, how it differs from green and renewable energy, whether nuclear is clean, with IPCC lifecycle emissions data.Non-Renewable Resources: Examples, Types and Why They Run OutNon renewable resources explained: fossil fuels, uranium and minerals, with sourced reserve and production data, examples and why they are finite.Renewable Energy Companies: The Largest Players and How the Industry WorksWho are the largest renewable energy companies? Generators like Enel, Iberdrola and Brookfield, plus top wind and solar manufacturers, with dated, sourced data.Renewable Energy Credits (RECs): What They Are and How They WorkRenewable energy credits (RECs) explained: what one REC is, how they are created, tracked and retired, what they cost, SRECs, and whether RECs are greenwashing.Renewable Energy Jobs: Careers, Salaries and How to Get StartedRenewable energy jobs explained: the main careers, BLS pay and growth data for wind and solar technicians, global job counts from IRENA, and how to get started.Renewable Resources: Definition, Examples and RenewabilityWhat is a renewable resource? Definition, examples of renewable resources beyond energy (water, timber, soil), renewable vs sustainable use, and a table.Renewable and Non-Renewable Energy: Key Differences ComparedRenewable and non renewable energy compared side by side: cost per MWh, lifecycle emissions per kWh, land use, reliability and the US and global power mix.Sustainable Energy: Definition, Criteria and ExamplesSustainable energy explained: the 5 tests a source must pass, how it differs from renewable energy, which sources qualify, and a scorecard with IPCC data.
Pros and cons
Advantages of Renewable Energy (and the Disadvantages to Weigh)Advantages of renewable energy weighed against its disadvantages: cost trends, emissions, intermittency, storage, land, minerals and grid limits, with data.Pros and Cons of Solar Energy for Homes and the GridPros and cons of solar energy for homes and the grid: installed cost, payback, 0.5%/yr degradation, net metering changes like California NEM 3.0, and recycling.Wind Energy Pros and Cons: Costs, Wildlife, Noise and Land UseWind energy pros and cons with sourced numbers: cost per MWh, capacity factor, bird and bat deaths, noise, land use and blade recycling.Wind vs Solar Energy: Cost, Efficiency, Land and Which Is BetterWind vs solar compared with sourced data: cost per MWh, capacity factor, efficiency, land use, emissions, wildlife and which suits a home or a grid.
Renewables at home
Geothermal Heat Pump: How It Works, Costs and PaybackGeothermal heat pump guide: closed and open loops, COP and ENERGY STAR ratings, installation cost, payback math and the end of the 25D tax credit.Wind Turbine for Home: Sizing, Costs and Whether It's Worth ItWind turbine for home guide: minimum wind speed, the 30-foot tower rule, cost per kW from DOE data, a worked output example and zoning tips.How Solar Panels Work: Photovoltaic Cells ExplainedPhotovoltaic cells explained: the photovoltaic effect, mono vs poly vs thin-film, TOPCon, HJT and perovskite cells, efficiency records, system parts.Clean Energy Charging on iPhone: What It Means and Should You Turn It Off?What Clean Energy Charging on iPhone means, how it uses grid carbon forecasts, whether it hurts battery health, how to turn it off, and how much CO2 it saves.Off-Grid Solar System: Components, Sizing and CostsOff grid solar system guide: components, step-by-step sizing from load to battery, array, controller and inverter, LiFePO4 vs lead-acid, and costs.Is Plug-In Solar Legal? Balcony Solar Laws by US State (2026)Plug-in and balcony solar laws by US state, checked against legislature texts: Utah, Virginia, Colorado, Vermont, Maine, Maryland, California and more.RV Solar System: How Much Solar Your RV or Camper NeedsRV solar system guide: size panels, batteries, charge controller and inverter for an RV or camper, with a worked 1.5 kWh/day example and the math for AC.Solar Panel Cost in 2026: Price per Watt, by System Size and StateHow much solar panels cost in 2026: LBNL median $3.60/W installed ($3.00/W cash), cost by system size, state factors, payback and the end of the 30% credit.Solar Panel Installation Permits: Process, Fire Setbacks and InterconnectionSolar panel installation permit guide: what the permit covers, the 33% roof rule and fire setbacks, NEC rapid shutdown, the 120% rule, inspections and PTO.
Electricity & EVs
How Much Does It Cost to Charge a Tesla? Home vs SuperchargerHow much it costs to charge a Tesla at home and at a Supercharger: per-model costs from EPA ratings, cost per mile, state prices and solar charging.How Much Does It Cost to Charge an Electric Car?How much it costs to charge an electric car at home and at fast chargers, with EPA data for popular EVs, EV vs gas cost per mile and state electricity prices.How to Lower Your Electric Bill: 15 Ways to Cut Home Electricity UseHow to lower your electric bill: where US home electricity goes (EIA), the biggest savings from heating, cooling and water heating, and what each tip is worth.What Is a Kilowatt-Hour (kWh)? Meaning, kW vs kWh and CostWhat is a kilowatt-hour? A plain-English guide to kWh meaning, kW vs kWh, what 1 kWh runs, average US home use, price per kWh by state and reading your bill.
FAQ
Frequently asked questions
Where should I start learning about renewable energy?
Start with our main guide to renewable energy on the homepage, then read renewable energy sources for a side-by-side comparison of solar, wind, hydropower, geothermal, biomass and ocean energy.
How are these guides researched?
Each guide uses primary sources such as the EIA, NREL, IEA, IRENA and Ember, states the year of every statistic and lists its sources at the end. See our editorial standards for details.
How often are the guides updated?
Each guide shows its last-updated date. Statistics and prices are refreshed when new official data is released, typically at least once a year.
Do the guides cover the downsides of renewable energy?
Yes. We have dedicated pros-and-cons guides for renewable energy overall, solar and wind, and each source guide covers costs, intermittency, land use and environmental impacts.
Can I use the guides for school projects?
Yes. You can link to and cite any guide. For academic work, also cite the primary sources listed at the end of each page.