Solar power has emerged as one of the most promising renewable energy technologies of the 21st century. As solar technology rapidly declines in cost and countries around the world move to decarbonize their energy systems, solar is poised to become one of the main pillars of a cleaner global economy. This article will provide an overview of solar photovoltaics, the current state of the solar industry, the environmental and economic benefits driving adoption, and what the future may hold for this important renewable energy resource.
How Do Solar Panels Work?
Solar photovoltaic panels are made up of solar cells, normally composed of silicon. When sunlight hits these cells, the absorbed photons knock electrons loose, allowing electricity to flow. This process of converting light (photons) to electricity (voltage) is called the photovoltaic (PV) effect. The PV effect was first discovered in 1839 by French physicist Edmond Becquerel. The first solar cell capable of generating enough electricity for a device was built in 1883 by American inventor Charles Fritts.
Early solar cells were very inefficient, converting less than 1% of the absorbed light into electricity. But in 1954, researchers at Bell Labs in the United States produced the first high-efficiency silicon solar cell. By the early 1960s, solar cells were being used to power some small devices like radios and watches. However, the cost was still far too high for widespread use. It took major leaps in materials science and manufacturing to improve efficiency and lower costs to the point where solar PV could become a major player in electricity generation.
Today’s solar cells typically utilize crystalline silicon or thin-film materials like cadmium telluride (CdTe). Silicon cells tend to be more efficient (15-22% on average), while thin-film cells are less expensive but convert a lower percentage of sunlight (7-13% on average). Solar cell technology and efficiency continues to steadily improve each year.
In order to produce useful amounts of electricity, solar cells are connected together and sealed behind glass to form durable solar panels. Solar panels can vary substantially in size, from small rooftop units to ground-mounted arrays spanning acres. The solar panels are wired together to combine the electricity generation capacity, which is measured in watts or kilowatts (kW). Utility-scale solar farms can now have capacities in the hundreds of megawatts (MW), rivaling traditional power plants.
A Critical Component of the Global Energy Transition
As the world moves aggressively to decarbonize electricity systems this century, solar power has rapidly emerged as one of the most critical technologies to enable the transition away from fossil fuels. The reasons behind solar’s enormous promise and recent expansion are simple – it is abundant, clean, and increasingly the most cost-effective electricity source in many markets.
There is no resource limitation for solar power. The sun bathes the Earth in more energy during 1 hour than all of humanity uses in an entire year. Solar PV only needs to capture a tiny fraction of this theoretically available solar resource to fully power modern civilization. Unlike finite fossil fuels, the sun’s energy will shine for billions of years to come.
Solar also generates electricity without emitting greenhouse gases or other pollutants associated with the burning of coal, natural gas, oil, or biomass. Widespread adoption of solar power is recognized as one of the most important steps toward halting global climate change this century.
Lastly, solar PV system costs have absolutely plummeted over the last decade, driven by economies of scale, advances in solar cell technology, and streamlining of global supply chains. According to Lazard’s industry-standard Levelized Cost of Energy (LCOE) analysis, the cost to generate solar power has dropped a staggering 90% since 2009. In most parts of the world today, building new large-scale solar is now the cheapest form of electricity generation by a significant margin.
Thanks to these economic, environmental, and resource advantages, installed solar capacity has skyrocketed all over the globe. Total worldwide solar PV capacity soared from only 8 gigawatts (GW) in 2008 to a staggering 580 GW by the end of 2019 – a 70-fold increase in just over a decade. This unprecedented growth is expected to continue for decades to come.
The plummeting price of solar energy has upended the conventional wisdom that renewable sources like solar and wind would always be niche players in electricity markets. In fact, solar and wind are now often the most cost-competitive options for new power generation. Recent projections suggest renewable energy (mainly from solar and wind) may supply up to 90% of total electricity demand worldwide by 2050.
Benefits of Transitioning to Solar Power
Widespread adoption of solar power would provide profound economic, social, political, and environmental benefits. Understanding these diverse benefits explains why solar energy receives such strong public support and why governments and businesses worldwide are committing substantial resources to solar expansion.
Environmental Benefits
The most straightforward benefit of transitioning from fossil fuels to solar power is the significant reduction of pollutants and greenhouse gas emissions. Solar PV generates electricity without producing air pollutants like particulates, nitrogen oxides (NOx), and sulfur dioxide (SO2) that harm public health. Switching coal-fired power to solar would annually prevent over 25,000 U.S. premature deaths from air pollution.
Solar plants also emit essentially no carbon dioxide (CO2) or other greenhouse gases responsible for climate change. Each MWh hour of electricity from coal produces about 1 ton of CO2 on average, while solar emits less than 0.1 tons. Replacing all coal and gas electricity globally with solar by 2050 could achieve nearly 50% of the emissions reductions needed this century to limit global warming to 1.5°C above pre-industrial levels.
While solar panels do require energy to manufacture, transport, and eventually decommission, researchers estimate solar can “pay back” this carbon footprint in only 1 to 4 years of operation through clean electricity generation. After paying back its carbon footprint, solar panels can continue delivering climate-friendly energy for decades.
Economic Prosperity
Although solar power was long considered too expensive for mainstream use, the staggering drop in PV system prices over the last ten years has made solar the most affordable electricity option in most areas. Given solar’s cost advantage over fossil fuels, transitioning to solar can grow economies and create millions of new jobs.
Solar energy can help stabilize and reduce electricity costs over time, protecting consumers and businesses from fossil fuel price volatility. Households and companies that install rooftop solar improve energy security and independence while reducing monthly utility bills. Utility-scale solar provides a low-cost option to meet grid demand and offset transmission loss. The modularity of solar also allows developing countries to rapidly expand electrification without the need for massive centralized infrastructure.
Manufacturing, transporting, installing, and maintaining solar panels worldwide already provides over 3 million well-paying jobs. Total solar industry employment could grow to over 20 million by 2050 in a high solar adoption scenario, per IRENA. And while fossil fuels risk becoming stranded assets as countries enact climate policies, solar offers stable returns on investment for decades to come.
National Security & International Relations
Overreliance on imported fossil fuels creates dangerous vulnerabilities to supply disruptions for importers and unwanted political leverage for autocratic petrostates. In contrast, developing domestic solar resources enhances national energy security and autonomy. Widespread adoption of solar shrinks fossil fuel markets, weakening the influence of petrostates and reducing financial flows supporting authoritarian regimes or armed conflicts.
Solar and other renewables can facilitate electrification of vulnerable developing communities, providing energy access critical for poverty alleviation and sustainable development. Decentralized solar solutions are often the fastest and cheapest option for rural electrification. Renewables also open possibilities for resource-sharing and electricity trade between nations, strengthening diplomatic ties through “energy interdependence” rather than reliance on particular suppliers.
Future Outlook
Solar power has already begun transforming electricity systems worldwide, but this is only the beginning of a decades-long energy transition. Total global solar PV capacity is currently around 600 GW but could grow over 16-fold to 10,000 GW by 2050 in a scenario aligned with limiting global warming to 1.5°C this century. Under this solar expansion trajectory, the sun would supply up to 20% of total worldwide electricity by 2030, 45% by 2040 and well over 50% by mid-century.
Realizing this bright vision for a solar-powered future will depend on sustained policy support and public and private investment in solar deployment and innovation. Governments must continue implementing strong decarbonization policies while investing in solar manufacturing capacity, workforce training, and upgrading grid infrastructure to handle high renewable penetration. Corporations will need to back up their strong sustainability commitments with actual investments and contracts that exponentially scale up solar in their operations and supply chains this decade.
The past decade of solar growth shows that consistent policy, public support, and large-scale investment can rapidly accelerate energy transitions that once seemed unlikely or far-off. While the fossil fuel incumbents will fight to protect their profits, the undeniable environmental and economic case for transitioning to renewable energy is simply too strong to ignore. Solar power offers one of the most indispensable technologies to sustainably and affordably power the world. The solar revolution has only just begun – we must seize this moment to ensure it shines brightly in coming decades.
