Solar energy powers everything from household appliances to industrial water treatment, and its reach is growing fast. Global installed solar capacity hit 2.25 terawatts by the end of 2024, and for the first time, solar generated more than 10% of the world’s electricity. Here’s where all that energy actually goes.
Powering Homes and Appliances
The most familiar use of solar energy is generating electricity for homes. Rooftop panels convert sunlight into power for refrigerators, air conditioning, ovens, computers, and entertainment systems. A standard 300-watt panel produces about 1.2 kilowatt-hours per day, which means a handful of panels can cover your kitchen. Six panels of that size can run a refrigerator (4 kWh/day), a dishwasher (8 kWh for a one-hour cycle), and a microwave (3 kWh for 15 minutes of daily use).
Air conditioning is the biggest residential power draw. Running a central AC unit for four hours consumes roughly 24 kWh, and a five-ton system needs around 20 panels to keep up. That’s a significant investment, but in hot, sunny climates it makes geographic sense: the hours of peak solar production overlap with the hours you need cooling most.
Heating Water and Indoor Spaces
Solar energy doesn’t have to become electricity first. Solar thermal systems capture heat directly and use it to warm water or air. Liquid-based solar collectors circulate water or a non-toxic antifreeze solution through panels on your roof, raising the fluid’s temperature by 10 to 20°F as it passes through. That heated fluid then warms your water tank or feeds into a central heating system.
Air-based solar heating works differently. Transpired air collectors, for example, are dark perforated metal plates mounted on a building’s south-facing wall. Sunlight heats the metal, and a fan draws outside air through tiny holes in the plate and into the building. Even on cold days, this setup can warm incoming air by as much as 40°F. Air collectors also start producing usable heat earlier and later in the day than liquid systems, so over a full heating season they can deliver more total energy despite being slightly less efficient per hour.
Solar-Powered Cooling
Heating and cooling systems account for roughly 50% of a building’s energy use in the United States, and between 15% and 30% in commercial buildings. Solar cooling flips the usual logic: instead of burning fossil fuels to remove heat, it uses solar thermal energy to drive an absorption chiller. These systems work by heating a refrigerant solution with solar-collected warmth, triggering a cycle that pulls heat out of indoor air. The result is air conditioning with significantly lower electricity consumption and greenhouse gas emissions than conventional HVAC.
Utility-Scale Electricity Generation
Beyond rooftops, massive solar farms feed power directly into the electrical grid. These come in two main forms. Photovoltaic farms use the same panel technology as residential systems, just at enormous scale. Concentrating solar power (CSP) plants take a different approach: mirrors focus sunlight onto a receiver that generates intense heat, which then drives a steam turbine.
CSP’s key advantage is built-in storage. The heat can be captured in molten salt, which retains thermal energy for hours after the sun sets. This makes CSP “dispatchable,” meaning grid operators can release the stored energy on demand rather than only when the sun shines. Early plants like Solar Two in California demonstrated this with molten salt storage, and newer facilities use organic oil as the heat-transfer fluid with molten salt reservoirs for overnight generation.
The economics keep improving. The levelized cost of electricity from a typical solar farm stood at $39 per megawatt-hour in 2025. That’s down from just over $60/MWh at the start of the decade, and BloombergNEF projects another 30% drop by 2035. For comparison, onshore wind sits at about $40/MWh and offshore wind at $100/MWh.
Charging Electric Vehicles
Solar-powered EV charging stations are becoming a practical link between renewable energy and transportation. These stations combine rooftop or canopy-mounted panels with battery storage and smart energy management. The system prioritizes solar power first, draws from its stationary battery second, and only pulls from the grid as a last resort.
Slow charging (up to 7 kW) works well on pure solar and battery power, topping off about 6 kWh per session, enough for a typical daily commute. Fast charging (7 to 22 kW) still leans on the grid, but the battery buffer reduces peak demand. Some stations also support vehicle-to-grid technology, where parked EVs send stored energy back to the grid during high-demand periods.
Solar panels are also being integrated directly onto vehicles. The available surface area is small, which limits how much energy they can capture, but the emissions reduction potential is striking: solar-powered EVs can cut emissions by 60 to 90% compared to grid-charged EVs, and over 90% compared to gasoline vehicles. Designers have explored solar integration on city buses, trains, vans, and even electric bicycles.
Agriculture and Irrigation
Agrivoltaics, the practice of combining solar panels and crop production on the same land, is one of the more creative applications. Elevated panels generate electricity overhead while crops grow underneath, and the partial shading actually reduces water evaporation from the soil. Studies show this dual use can increase land productivity by 35 to 75%, and water productivity improves enough that farms can cut irrigation by 20% while accepting only a 10% yield decrease.
Solar-powered water pumps add another layer. A dedicated pumping unit, running independently from the main panel array, ensures crops always get water without competing with energy production. These pumps pair well with precision irrigation systems like drip lines, delivering water exactly where it’s needed. For off-grid farms, this autonomy is transformative: no diesel generators, no utility connection, just sunlight driving water from wells to fields. The systems scale easily too, with additional pumping units added as farms expand.
Desalination and Water Treatment
Nearly 60% of the global population lives away from coastlines, making freshwater access a persistent challenge. Solar energy is increasingly used to power desalination, the process of removing salt and contaminants from water. The two dominant methods are membrane-based reverse osmosis, which runs on electricity, and multi-effect distillation, which uses heat directly. Together they account for over 90% of installed desalination capacity worldwide.
Solar-powered desalination is especially promising for inland communities dealing with brackish groundwater, agricultural runoff, or industrial wastewater. Some systems push toward zero liquid discharge, concentrating the leftover brine until only solid minerals remain. Those recovered minerals, including materials relevant to battery manufacturing, could eventually offset operating costs, though that side of the technology is still developing.
Portable and Off-Grid Power
In remote areas without reliable grid access, solar fills the gap at every scale. Portable solar chargers weigh a few pounds and keep smartphones, tablets, and cameras running during camping trips or fieldwork. Larger portable solar generators, with capacities of several kilowatt-hours, serve as emergency backup during power outages or natural disasters, providing enough juice for lights, communication devices, and small appliances.
At the community level, off-grid solar installations bring electricity to areas that lack conventional energy infrastructure entirely. Basic lighting, phone charging, and telecommunications equipment can all run on modest panel arrays with battery storage, eliminating dependence on diesel fuel that’s expensive to transport and polluting to burn.