Compare
Compare energy sources
Qualitative comparison of major electricity sources. Numeric claims are omitted or flagged when they cannot be verified here.
Counts among selected sources — not invented percentages
| Field | Solar | Wind | Hydro | Nuclear fission | Geothermal | Biomass | Natural gas | Coal |
|---|---|---|---|---|---|---|---|---|
| Renewable | Yes | Yes | Yes | No | Yes | Yes | No | No |
| Fuel / resource | Sunlight | Wind | Water in the hydrological cycle | Uranium (sometimes MOX) | Earth heat | Organic matter | Natural gas | Coal |
| Typically dispatchable | No | No | Yes | Yes | Yes | Yes | Yes | Yes |
| Direct CO2 from the energy conversion | None from the photovoltaic or CSP conversion step | None from the conversion step | None from the turbine; some reservoirs emit methane, especially in the tropics | None from fission; lifecycle emissions are from the fuel cycle and construction | Typically low; some fields release dissolved gases | Combustion emits CO2; net climate effect depends on feedstock and land use | Significant; lower than unabated coal per unit electricity in typical plants, but not zero. Methane leaks matter. | Highest among major thermal electricity fuels at the stack |
| Output pattern | Follows daylight and weather | Varies with wind resource; offshore often more consistent than many onshore sites | High when water is available; droughts reduce output | Designed for high availability; refuelling outages for most LWRs | High where the resource is well characterized | Can be dispatched if fuel is stored | High; often used for flexibility | Can be high; less flexible than gas in many plants |
| Efficiency note | Module and plant efficiencies vary by technology; do not treat a single number as universal | Aerodynamic and electrical losses; Betz limit is an upper bound on rotor extraction, not plant efficiency | Among the highest conversion efficiencies of any major electricity source when head and machine are well matched | Thermal efficiency similar in order of magnitude to other steam plants; exact values are design-specific | Limited by resource temperature (thermodynamics) | Wide range by technology (heat-only vs CHP vs liquid fuels) | Combined-cycle plants are among the more efficient fossil generators; simple-cycle less so | Steam-cycle efficiencies vary; older plants are lower |
| Capacity factor note | Climate- and design-dependent; typically lower than thermal baseload plants | Site-dependent | Depends on hydrology and whether the plant is peaking or baseload | Often high among large thermal plants; verify current regional statistics before quoting a numberNeeds verification | Often high for hydrothermal plants | Can be high if fuel is available | Varies from peaking to baseload | Historically high where coal was baseload; now often displaced in some markets |
| Plant life note | Modules often warrantied for about 25–30 years; treat as typical commercial practice | On the order of a couple of decades for many turbines; verify project-specific data | Civil works can last many decades | Many plants licensed for 40 years with possible extensions; not universalNeeds verification | Wells may need makeup drilling over decades | Similar to other thermal plants if maintained | Decades with maintenance | Decades |
| Land-use note | Utility PV needs significant area per energy; rooftop uses existing structures | Spacing between turbines; land between can often remain in other use | Reservoirs can inundate large areas; run-of-river much less so | Compact energy density at the plant site; mining is additional | Relatively compact for the energy delivered | Can be large if purpose-grown crops are used | Compact plants; upstream production has a larger footprint | Plant plus mining and ash handling |
| Storage coupling | Often paired with batteries or other flexible resources | Helps firm variable output; not strictly required at low grid shares | Reservoirs store energy; pumped storage is dedicated storage | Not required for variability of the source itself; grid still needs balancing | Not usually required for resource variability | Fuel itself is a chemical store | Linepack and gas storage support the fuel, not the electricity | Coal piles store fuel |
| Advantages | Modular, no fuel combustion, rapid to deploy at many scales | No fuel, scalable farms, strong resources in many regions | Mature, flexible (with storage), long-lived | Low-carbon firm power, high energy density | Firm renewable heat and power where geology allows | Dispatchable, can use wastes | Flexible, relatively rapid to build compared with nuclear, lower CO2 than coal at the stack | Dispatchable, established infrastructure in some regions |
| Challenges | Night-time gap, weather, materials and recycling | Variability, siting, wildlife, grid connection | Geography, ecology, sedimentation, social displacement | Cost, waste, accidents (rare but severe), public acceptance | Exploration risk, location, induced seismicity for some EGS | Sustainability, air quality, energy density | Fossil CO2, methane, price volatility, import dependence in some countries | Climate, air pollution, mining impacts, ash |
- This table is educational, not a substitute for lifecycle-assessment databases.
- Do not invent a single global efficiency or grams-CO2-per-kWh figure here.
- Fusion is omitted because it is not a commercial electricity source as of 2026.