What Is Renewable Energy?

Renewable energy refers to energy sources that are natural, continuous, and large. This includes solar energy, wind energy, water energy, geothermal energy, and certain biofuels. The downside to renewable sources of energy is that they generally require a substantial amount of infrastructure to extract appreciable power. For example, collecting solar energy requires expensive solar panels. Harvesting wind energy requires wind turbines. Getting energy from flowing water requires dams, and so on.

Unlike fossil fuels, which are finite and release harmful emissions into the atmosphere when burned, renewable energy sources are environmentally friendly and sustainable. Many countries are investing in renewable energy to reduce their dependence on fossil fuels and move towards a more sustainable future. For example, solar panel installations convert sunlight into electricity, while wind turbines harness wind power. Hydropower plants generate electricity from water flow, and biogas facilities turn organic matter, such as manure into methane gas that can be used for heating or powering vehicles.

Today, renewable energy is poorly exploited. Most countries get less than 10% of their power from renewable energy sources. Fossil fuels are easier to come by, and they currently return more power per dollar invested in extracting them. Certain countries, like Iceland and Norway, get as much as 99% of their power from renewable energy sources, but this is because they are located conveniently in areas where there is abundant geothermal activity. For other countries to transition to renewable energy will require significant investments and starting costs.

Investments in renewable energy have been increasing since the environmental movement of the 1960s and 70s, and more recently due to renewed concerns about global warming and Peak Oil. Fossil fuels pollute the earth, are limited in nature, and are controlled by undemocratic states in politically volatile regions. Using our limited quantities of fossil fuel energy to invest in a renewable energy infrastructure seems like a wise collective decision for the human species to make.

Ultimately, the renewable energy source that will offer the greatest amount of power is solar energy. There are millions of venture capital and government dollars being invested in start-ups seeking to boost the efficiency and reduce the cost of solar cells, and progress is being made. Solar furnaces, which condense the sun's rays into a focus with mirrors, then use that heat to boil liquid and run turbines, are an even more efficient means of harnessing solar energy than conventional solar panels. The surfaces of the world's oceans are largely unused, and life in certain parts of the sea is very scarce, making them ideal venues for deploying floating solar panels that power the world's cities. Eventually, we will exploit the gargantuan volumes of space to set up solar panels and beam power to where it is needed.

In the meantime, we can extract appreciable quantities of energy from other renewable sources such as water and wind. For example, the recently completed Three Gorges Dam in China will produce 18 gigawatts of continuous power when all its generators are installed. This will supply about 3% of the national demand for electricity. The project cost roughly under a billion US dollars (USD).

Frequently Asked Questions

What exactly is renewable energy?

Renewable energy is derived from natural processes that are replenished constantly. This includes sunlight, wind, water movement, geothermal heat, and biological processes. Unlike fossil fuels, which can take millions of years to form, renewable resources can be restored naturally at a rate that is sustainable for ongoing use.

Why is renewable energy important for the environment?

Renewable energy is crucial for the environment because it produces little to no greenhouse gases or pollutants. According to the U.S. Environmental Protection Agency, renewable energy sources can help reduce the occurrence of harmful air pollution, mitigate climate change by curbing carbon dioxide emissions, and conserve water resources compared to conventional power generation methods.

What are the most commonly used sources of renewable energy?

The most commonly used sources of renewable energy include solar power, wind energy, hydroelectric power, biomass, and geothermal energy. Solar and wind are among the fastest-growing renewable sectors, with the International Energy Agency reporting significant increases in capacity and installation of solar panels and wind turbines globally.

How does renewable energy contribute to economic growth?

Renewable energy contributes to economic growth by creating jobs in manufacturing, installation, and maintenance of renewable energy technologies. The renewable energy sector has been growing rapidly, with the International Renewable Energy Agency reporting that jobs in the sector reached 11.5 million globally in 2019, indicating a positive trend in employment opportunities.

Can renewable energy replace fossil fuels completely?

While renewable energy has the potential to replace a significant portion of fossil fuels, the transition requires substantial investment in technology, infrastructure, and grid adaptation. According to the International Energy Agency, renewables are set to account for almost 95% of the increase in global power capacity through 2026, showing a strong move towards replacing fossil fuels.

What are the challenges associated with the adoption of renewable energy?

The adoption of renewable energy faces challenges such as the intermittency of sources like solar and wind, the need for large upfront investments, and the requirement for energy storage solutions. Additionally, transitioning the existing energy infrastructure to accommodate renewables and ensuring a stable energy supply are significant hurdles that need to be addressed.