Viewpoints

About Renewable Energy Technologies

Modern renewable energy technologies have become mainstream as their costs have declined dramatically in global energy markets. Renewables are increasingly the most competitive and sustainable power-generation alternatives to today's dominant fossil-fuel and nuclear technologies. Researchers continue to make advances in a broad range of renewable technologies for electricity generation, transport fuels, and heating and cooling. Renewable technologies draw on continuously replenished energy resources—including heat and light from the sun, wind, biomass, falling water, heat from inside the earth, and ocean energy. These resources are typically large and dispersed, and their energy is often convertible with little environmental impact and low- and no-carbon emissions.

Renewable energy technologies—led by solar PV, wind power, and hydropower—continue to grow rapidly in response to a confluence of drivers, including declining system costs, growth in energy demand in developing countries, environmental concerns about pollution and global warming, the desire for greater energy security, fossil-fuel-price uncertainty, and technology advances that improve the performance of renewable systems. Renewables are also stimulating innovation and economic-growth opportunities. Government policies continue to support technology development and deployment and lower market barriers. Nearly every country now provides some type of renewable energy target or other support policy, and policies in countries such as Germany, Japan, the United States, and China have proved extremely successful in encouraging deployments. Onshore-wind, solar PV, biomass, geothermal, and hydropower technologies are competitive with conventional energy supplies without subsidies in many regions. Competitive bidding programs worldwide are attracting record low prices and high volumes for solar and wind power, in particular.

Renewable energy technologies will reshape world energy markets for years to come. Global investments in renewable power and fuels—especially solar and wind power—reached $305 billion in 2018. For the fourth year in a row, investment in new renewable-power capacity exceeded combined investments in fossil-fuel and nuclear power capacity. Growth opportunities depend on local conditions—the renewable resource base, government support and energy economics, market factors, and institutional constraints. As solar-PV prices continue to plummet, grid-connected and off-grid adoptions are accelerating and creating opportunities for materials, component, and system suppliers (especially for crystalline-silicon PV technology) and developers. The concentrating-solar-power industry is much smaller but is expanding in sunny regions worldwide. Wind-turbine suppliers continue to see steady growth, led by China, and offshore-wind markets are spreading worldwide. Biofuels producers have opportunities in countries that mandate their use—but future growth depends on the commercialization of more sustainable biofuels. Large and small hydropower applications continue to expand to meet energy needs, especially in developing countries, and pumped-hydro energy storage is seeing growing use to complement solar and wind technologies. Geothermal power and heating markets are seeing moderate growth and have untapped potential in many countries. Ocean-tidal and wave-energy technologies have reached early commercialization and have significant long-term potential. All these technologies have the potential to offer clean new sources of low-carbon energy, provide sustainable economic-development opportunities, and improve the standard of living for people in rural areas. As more countries approach the large-scale use of renewables, stakeholders must also assess the economic, environmental, and social trade-offs—such as land-management issues—and integration issues associated with each technology.