Renewables and Scale
Renewables include a range of energy sources including solar power, onshore and offshore wind, tidal and wave power, geothermal energy, biofuels including biomass, biogases and algae, and in some narratives hydropower is included. All of these energy sources have the potential to generate electricity, but the problem faced by all of them is scale and cost. Building renewable energy on the scale required to meet the energy needs of the growing world population in a way that is cost effective is a huge challenge. So far, solar and wind are emerging as the clear winners. Costs have been reduced significantly as the industry has scaled up. But the sun does not always shine, and the wind does not always blow. The problem of intermittency requires that backup energy sources — from energy storage or low carbon gases — are available.
Renewable energy is widely seen as a panacea for climate change. Breakneck growth has proved their viability, but scaling up to replace the approximately 80% of energy that derives from fossil fuels will be an enormous challenge.
From Little Seeds
Only 5% of the world’s energy comes from renewable sources like solar and wind power, but that’s a significant increase from just 2% at the start of the last decade (2010). The share of renewables in overall primary energy demand varies greatly by geographical region, from negligible amounts in Russia and the CIS to around 10% of the total in Europe and the Americas. China was the world’s biggest investor in renewable energy in recent years, and renewables now account for nearly 5% of the energy used in the world’s most populous country. Whether this will continue to grow will be influenced heavily by politics: the Paris Agreement in 2015 followed a historic alignment of Chinese and US interests, but this is now threatened by the trade war between the two superpowers. The trajectory of economic growth after the Covid-19 virus and global lockdowns is also at stake.