Renewables: Not Fast Enough
Updated: Mar 18, 2021
Modern society is utterly dependent on carbon-based/fossil fuels (coal, oil and gas). Yet our consumption of these fuels means that we dump billions of tons of CO2 and other greenhouse gases into the atmosphere every year. If we do not change course the consequences will be catastrophic. Therefore, at the heart of virtually all climate change proposals such as ‘Net Zero by 2050’ is a plan to switch from fossil fuels to alternative sources of energy that do not emit greenhouse gases. These alternatives include solar, wind, hydro-electric and ocean (wave and tidal) power.
Most of these plans contain within themselves an unspoken presumption that we can simply switch to a modified way of living — for example, from gasoline-powered cars to electric vehicles — and continue our current energy-profligate lifestyle. Few ‘Net Zero’ programs call for us to make a significant cut in our material standard of living, or to live a simpler lifestyle.
The assumption that we can simply switch from fossil fuels to “green” energy sources and continue on our merry way is unrealistic. But, the fact that the transition will be more difficult than generally supposed does not mean that we give up on making the switch. However, we do need to temper our expectations with engineering, project management and financial realities.
In this series of posts we consider some of the difficulties the transition entails. The first post — The Renewables Paradox — discussed the fact that renewables are growing much more quickly than other energy sources, but, paradoxically, their share of the overall energy mix is declining. In this post we look at the speed with which renewables are being adopted.
In this post we show that, although the use of renewable energy sources is growing very quickly, it is not nearly fast enough to meet the ‘Net Zero’ goals to which many governments and corporate entities are now committed. The following Chart and Table are based on the BP report World Energy Outlook (2020) to provide the data for this analysis.
The Table shows that renewables currently supply around 29 exajoules per annum. If we assume minimal growth in nuclear and hydro, then renewables will have to supply about 460 exajoules annually by the year 2050, assuming no economic growth. This is equivalent to an additional 14 exajoules per annum every year. In other words, we would have to install the entire existing capacity of solar and wind every two years for the next 30 years. Looked at another way, solar and wind will have to grow between three and four times faster than they are now every year for the next 30 years.
If we assume that energy consumption increases by 1.5% per annum in order to match hoped-for economic growth, then renewables will need to supply about 720 additional exajoules of energy. In other words, for every solar or wind farm that we have now, we will have to have installed 26 such facilities by the year 2050. This is, to say the least, a challenging goal.