How Does Solar Work? | Department of Energy

How Does Solar Work? | Department of Energy
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How Does Solar Work?
The amount of sunlight that strikes the earth's surface in an hour and a half is enough to handle the entire world's energy consumption for a full year. Solar technologies convert sunlight into electrical energy either through photovoltaic (PV) panels or through mirrors that concentrate solar radiation. This energy can be used to generate electricity or be stored in batteries or thermal storage.
Below, you can find resources and information on the basics of solar radiation,
photovoltaic
and
concentrating solar-thermal power
technologies, electrical grid
systems integration
, and the non-hardware aspects (
soft costs
) of solar energy. You can also learn more about how to
go solar
and the
solar energy industry
. In addition, you can dive deeper into solar energy and learn about how  the U.S. Department of Energy Solar Energy Technologies Office is driving innovative
research and development
in these areas.
Solar Energy 101
Solar radiation is light – also known as electromagnetic radiation – that is emitted by the sun. While every location on Earth receives some sunlight over a year, the amount of solar radiation that reaches any one spot on the Earth’s surface varies. Solar technologies capture this radiation and turn it into useful forms of energy.
Learn about the basics of solar radiation
There are two main types of solar energy technologies—photovoltaics (PV) and concentrating solar-thermal power (CSP).
Photovoltaics Basics
You're likely most familiar with PV, which is utilized in solar panels. When the sun shines onto a solar panel, energy from the sunlight is absorbed by the PV cells in the panel. This energy creates electrical charges that move in response to an internal electrical field in the cell, causing electricity to flow.
Solar Photovoltaic Technology Basics
Learn the basics of how photovoltaic (PV) technology works with these resources from the DOE Solar Energy Technologies Office.
about Solar Photovoltaic Technology Basics
Solar Photovoltaic System Design Basics
Solar photovoltaic modules are where the electricity gets generated, but are only one of the many parts in a complete photovoltaic (PV) system.
about Solar Photovoltaic System Design Basics
PV Cells 101: A Primer on the Solar Photovoltaic Cell
Part 1 of the PV Cells 101 primer explains how a solar cell turns sunlight into electricity and why silicon is the semiconductor that usually does it.
about
PV Cells 101: A Primer on the Solar Photovoltaic Cell
December 3, 2019
Solar Performance and Efficiency
Improving photovoltaic (PV) efficiency is a key goal of research and helps make PV technologies cost-competitive with conventional sources of energy.
about
Solar Performance and Efficiency
April 7, 2025
Concentrating Solar-Thermal Power Basics
Concentrating solar-thermal power (CSP) systems use mirrors to reflect and concentrate sunlight onto receivers that collect solar energy and convert it to heat, which can then be used to produce electricity or stored for later use. It is used primarily in very large power plants.
Concentrating Solar-Thermal Power Basics
Learn the basics of how concentrating solar-thermal power (CSP) works with these resources from the DOE Solar Energy Technologies Office.
about
Concentrating Solar-Thermal Power Basics
April 3, 2025
Thermal Storage System Concentrating Solar-Thermal Power Basics
One challenge facing solar energy is reduced energy production when the sun sets or is blocked by clouds. Thermal energy storage is one solution.
about
Thermal Storage System Concentrating Solar-Thermal Power Basics
December 10, 2021
Power Tower System Concentrating Solar-Thermal Power Basics
In power tower concentrating solar power systems, several flat, sun-tracking mirrors focus sunlight onto a receiver at the top of a tall tower
about
Power Tower System Concentrating Solar-Thermal Power Basics
October 27, 2020
Linear Concentrator System Concentrating Solar-Thermal Power Basics
Linear concentrating solar power (CSP) collectors capture the sun's energy with large mirrors that reflect and focus the sunlight on a linear receiver
about
Linear Concentrator System Concentrating Solar-Thermal Power Basics
December 4, 2020
Systems Integration Basics
Solar energy technology doesn’t end with electricity generation by PV or CSP systems. These solar energy systems must be integrated into homes, businesses, and existing electrical grids with varying mixtures of traditional and other renewable energy sources.
Solar Systems Integration Basics
Learn the basics of how solar energy technologies integrate with electrical grid systems through these resources from the DOE Solar Energy Office.
about
Solar Systems Integration Basics
April 3, 2025
Solar Integration: Inverters and Grid Services Basics
This page explains what an inverter is and why it's important for solar energy generation.
about
Solar Integration: Inverters and Grid Services Basics
March 31, 2025
Solar Integration: Distributed Energy Resources and Microgrids
This resource page looks at ways to ensure continuous electricity regardless of an unforeseen event are by using distributed energy resources.
about
Solar Integration: Distributed Energy Resources and Microgrids
October 6, 2022
Solar Integration: Solar Energy and Storage Basics
Storage helps solar contribute to the electricity supply even when the sun isn’t shining by releasing the energy when it's needed.
about
Solar Integration: Solar Energy and Storage Basics
March 31, 2025
Soft Costs Basics
A number of non-hardware costs, known as soft costs, also impact the cost of solar energy. These costs include permitting, financing, and installing solar, as well as the expenses solar companies incur to acquire new customers, pay suppliers, and cover their bottom line. For rooftop solar energy systems, soft costs represent the largest share of total costs.
Solar Soft Costs Basics
Learn the basics of what solar soft costs are and how they impact solar energy adoption with resources from the DOE Solar Energy Technologies Office.
about
Solar Soft Costs Basics
October 16, 2025
Community Solar Basics
As the solar energy market expands, alternative business models like community solar are gaining popularity.
about
Community Solar Basics
April 16, 2026
Solar Workforce Development
Solar workforce development includes online training, on-the-job training, curriculum development, and other activities that prepare people for solar.
about
Solar Workforce Development
December 15, 2025
Going Solar Basics
Solar energy can help to reduce the cost of electricity, contribute to a resilient electrical grid, create jobs and spur economic growth, generate back-up power for nighttime and outages when paired with storage, and operate at similar efficiency on both small and large scales.
Homeowner’s Guide to Solar
When it comes to installing solar, our resources can help you determine the best options.
about
Homeowner’s Guide to Solar
December 17, 2025
Farmer's Guide to Going Solar
If you are an agricultural land owner and are considering your options to go solar, here are some resources to help you decide what’s best for you.
about
Farmer's Guide to Going Solar
May 29, 2025
Solar Rooftop Potential
To help consumers quantify the potential benefits of going solar, national laboratories and private companies have developed a number of tools.
about
Solar Rooftop Potential
October 14, 2025
Community Solar Basics
As the solar energy market expands, alternative business models like community solar are gaining popularity.
about
Community Solar Basics
April 16, 2026
Solar Industry Basics
Solar energy systems come in all shapes and sizes. Residential systems are found on rooftops across the United States, and businesses are also opting to install solar panels. Utilities, too, are building large solar power plants to provide energy to all customers connected to the grid.
Quarterly Solar Industry Update
Each quarter, NREL conducts a presentation of technical trends within the solar industry.
about
Quarterly Solar Industry Update
March 31, 2025
Solar Energy Resources for Job Seekers
These resources help those looking to find employment in the hundreds of thousands of jobs in the U.S. solar industry.
about
Solar Energy Resources for Job Seekers
December 18, 2024
Dive Deeper
Learn more about the innovative research the Solar Energy Technologies Office is doing in these areas.
Photovoltaics
about Photovoltaics
Concentrating Solar-Thermal Power
about Concentrating Solar-Thermal Power
Systems Integration
about Systems Integration
Soft Costs
about Soft Costs
Manufacturing and Competitiveness
about Manufacturing and Competitiveness
In addition to this basic information about solar energy, you can find more
solar energy information resources
here.
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