Key Milestones in the History of Solar Energy

The history of solar energy stretches back further than most people realize — long before solar panels, silicon solar cells, or the modern solar energy industry existed.

In one sense, human beings have been using solar energy since their earliest days. The first time a person warmed themselves in the sun after a chilly night, they were using solar energy.

Of course, history is filled with examples of early civilizations using the power of the sun for more sophisticated purposes. The ancient Egyptians, for example, let water heat during the day in black-lined pools and then piped the hot water through their homes at night for heat.

Even earlier, ancient Greeks and Romans used burning mirrors and massive glass windows to concentrate the sun's heat and light, torches, or fires for ceremonial purposes.

Others built solar ovens and used solar thermal techniques to harness the sun's energy for cooking and warmth. These were some of the earliest known attempts to harness solar power — crude by today's standards, but remarkable for their time.

But for our purposes here at TerraSol Energies, the history of solar energy begins with the invention of the photovoltaic cell, which creates the electricity we tap to power our homes and businesses.

Here’s a brief outline of the development of modern solar energy, as compiled by experience.com.

Key Milestones in The History of Solar Energy

1876 — The Photoelectric Effect and Selenium Wafers

The history of photovoltaic energy (a.k.a. solar cells) started way back in 1876. William Grylls Adams, along with a student of his, Richard Day, discovered that when selenium was exposed to light, it produced electricity.

An electricity expert, Werner von Siemens, stated that the discovery was "scientifically of the most far-reaching importance." The selenium cells were not efficient, but it was proved that light, without heat or moving parts, could be converted into electricity.

This discovery laid the groundwork for the photoelectric effect — the principle that light striking certain materials can cause them to release electrons, generating an electric current.

It was the first proof that it was possible to convert sunlight directly into usable solar electricity using two metal electrodes and selenium wafers, without any combustion or moving parts.

1953 — Silicon Solar Cells and the Bell Solar Battery

In 1953, Calvin Fuller, Gerald Pearson, and Daryl Chapin discovered the silicon solar cell. This cell actually produced enough electricity and was efficient enough to run small electrical devices.

The New York Times stated that this discovery was "the beginning of a new era, leading eventually to the realization of harnessing the almost limitless energy of the sun for the uses of civilization."

This breakthrough — known as the Bell Solar Battery — was the first photovoltaic cell practical enough for real-world use. Unlike earlier selenium wafers, the new silicon cells had a much higher energy conversion rate, making them the true foundation of modern photovoltaic technology and the broader solar energy industry. (Related: A Strategic Guide to Residential Energy Storage To Save More)

1956 — First Solar Cells Available Commercially

The year is 1956, and the first solar cells are available commercially. The cost, however, is far from the reach of everyday people. At $300 for a 1-watt solar cell, the expense was far beyond anyone’s means.

1956 started showing us the first solar cells used in toys and radios. These novelty items were the first items to have solar cells available to consumers.

The first solar panels of this era were basic by today's standards — small, fragile, and expensive — but they marked the beginning of solar-powered devices reaching the public.

Inventors and manufacturers began registering patents for solar-powered engines, solar-powered steamboats, and early solar array concepts around this period, signaling that the solar industry saw a future beyond novelty items.

Late 1950s–1960s — Solar Powers Outer Space

In the late 1950s and early 1960s, satellites in the USA's and the Soviets' space programs were powered by solar cells, and in the late 1960s, solar power was basically the standard for powering space-bound satellites.

The demands of outer space — where connecting to any grid was impossible — made PV systems the only viable hybrid power source for satellites.

The United States government and the National Renewable Energy Laboratory began investing heavily in solar research during this period, recognizing that photovoltaic systems that could work in the harsh conditions of outer space could eventually be adapted for use on Earth.

A remote-controlled solar airplane and early power satellites were among the concepts explored during this era of rapid solar power technology development.

Early 1970s — Exxon Drives Down the Cost

In the early 1970s, a way to lower the cost of solar cells was discovered. This brought the price down from $100 per watt to around $20 per watt. This research was spearheaded by Exxon. Most offshore oil rigs use solar cells to power the waning lights on the top of the rigs.

The irony of an oil company advancing solar technology wasn't lost on the solar energy industry — but it reflected the practical reality that even fossil fuel infrastructure needed reliable off-grid power in remote locations.

The Energy Policy Act and growing public awareness of dependence on fossil fuels further accelerated solar research through the late 1970s. (Related: Rising Utility Costs: Understanding Why PECO Is Raising Electric Rates in 2026)

1970s–1990s — Solar Spreads Across the Globe

The period from the 1970s to the 1990s saw quite a change in the usage of solar cells. They began showing up on railroad crossings, in remote places to power homes, and Australia used solar cells in their microwave towers to expand their telecommunication capabilities. Even desert regions saw solar power bring water to the soil where line-fed power was not an option.

This era also saw major milestones in solar technology: the Solar Challenger became the first solar-powered aircraft to cross the English Channel, and Solar Impulse projects demonstrated that solar-powered flight over long distances was achievable.

Photovoltaic systems were installed on a New York City rooftop as part of early residential solar trials, and building-integrated photovoltaics — where solar panels are built directly into glass materials and building surfaces — began to emerge as a concept.

Solar PV costs continued to fall, making installing solar increasingly viable for everyday homeowners. (Related: The End of the Tax Incentive Is Not the End of Residential Solar in PA | PECO Unveils New Solar Incentive for Businesses)

Today, we see solar cells in a wide variety of places. You may see solar-powered cars. There is even a solar-powered aircraft that has flown higher than any other aircraft with the exception of the Blackbird. With the cost of solar cells well within everyone’s budget, solar power has never looked so tempting.

Recently, new technology has given us screen-printed solar cells, and a solar fabric that can be used to side a house, even solar shingles that install on our roofs. International markets have opened up, and solar panel manufacturers are now playing a key role in the solar power industry.

Modern, efficient solar panels can now achieve energy conversion rates that early pioneers could only dream of. Lithium-ion batteries and advanced solar batteries make it possible to store electricity generated during the day for use at night.

Residential solar systems — once the domain of early adopters — are now a mainstream choice for homeowners looking to generate electricity, cut utility costs, and reduce their carbon footprint.

The solar energy industry has grown from a curiosity into one of the world's fastest-expanding renewable energy sectors. (Related: PECO Residential Solar Power Rebate: How TerraSol Energies Makes Going Solar Easy)

TerraSol Energies is a family-run business that has been serving the Tri-State area (PA, NJ, DE) since 2009.  With more than 40 years of collective global project management experience, TerraSol engineers are some of the best in the business – and ready to help.

Check out what our customers have to say and then contact us to set up a free consultation by calling 888-873-9995.

Frequently Asked Questions

What is the history of the solar system?

While astronomy studies the planetary solar system, the first modern solar power system dates back to 1876. Scientists William Grylls Adams and Richard Day discovered the photoelectric effect using selenium, paving the way for the highly efficient residential and commercial solar arrays we use today.

Who invented the first solar energy?

While ancient civilizations utilized passive heat from the sun, William Grylls Adams and Richard Day created the first solar electricity in 1876 using selenium wafers. In 1953, Calvin Fuller, Gerald Pearson, and Daryl Chapin invented the first practical silicon solar cell, forming the foundation of modern solar panels.

What is the history of first solar?

The first commercial solar cells were introduced in 1956. Initially costing an expensive $300 per watt, they were primarily used in novelty toys and radios. By the 1960s, the technology had advanced rapidly to become the standard power source for space-bound satellites before expanding to commercial use.

What is the history of solar time?

While "solar time" usually refers to ancient sundials, the timeline of solar power is quite different. It spans from early Greeks and Romans harnessing passive solar heat, to the 1876 discovery of the photoelectric effect, and finally to the advanced photovoltaic panel technology powering modern homes globally.