Professor Andrew Blakers, 2023 winner of the Queen Elizabeth Prize for Engineering
More new solar generation capacity is being built than everything else combined, compelling evidence that solar energy is the cheapest energy today, according to Professor Andrew Blakers.
Solar is growing much faster than any other energy technology in history, fast enough to completely displace fossil fuels from the global economy before 2050.
The rise and rise of cheap solar is the best hope for rapidly mitigating climate change, however, we need to get to zero fossil fuel use faster than 2050 to reduce the extent of climate damage.
Global solar capacity passed 1 Terawatt (1,000 Gigawatts) in 2022. At current growth rates, this will increase to 6 Terawatts around 2031, which is larger than the combined total of coal, gas, nuclear and hydro.
Relatively few new fossil-fuelled power stations are being built. This means that the global fleet is aging, and most will retire by mid-century.
Global generation capacity additions (2018-2022)
The world will naturally move to a solar/wind energy system provided that we stop buying fossil fuel machines.
Pathfinding
Most solar panels use PERC solar cell technology. The developers of this elegant technology were recently awarded the Queen Elizabeth Prize for Engineering.
All the leading countries for per capita solar and wind generation are in Europe – except for Australia.
In Australia, 99% of new generation capacity is solar and wind because it is cheap. Unlike European countries, Australia cannot share electricity across national boundaries and therefore the country must cope alone with rapidly increasing levels of solar and wind and is finding it to be relatively straightforward.
Australia currently procures 40% of its electricity from renewables (mostly solar and wind) and has a highly credible pathway to reaching its 82% renewable electricity target by 2030.
Global solar generation capacity assuming continued 20% growth rate in annual deployment
Already, the Australian grid regularly passes 65% solar fraction. Grid stability is excellent, and more solar and wind in the grid produces lower (not higher) prices.
A key feature of Australia’s energy transition is an open electricity market, which allowed companies and millions of households to discover that solar and wind are cheap. Australia’s location at low-moderate latitude is similar to where 80% of the global population lives. Most of the world’s population can readily follow the Australian pathway.
Where will rapid growth take us?
Global solar capacity is growing at 20% per year. Where can this growth take us?
Per capita solar and wind generation in 2022.
Complete elimination of fossil fuels is straightforward – electrify everything using solar and wind:
- Electric vehicles replace conventional vehicles;
- Electric heat pumps replace gas space and water heating in buildings;
- Electric furnaces replace gas burners in factories;
- Electrolysis of water produces hydrogen atoms for the chemical industry: ammonia, metals, plastics, synthetic aviation fuel.
Most fossil fuel use will vanish 15 years after we stop buying fossil fuel machines – by replacing retiring fossil fuel machines with electric versions. We can start this right now.
Electricity production needs to double to service the first three items above. In countries with a significant chemical industry, electricity production might need to triple.
Electricity consumption is strongly correlated with affluence. Let’s paint a desirable scenario. By mid-century:
- Developing countries catch up with Europe for per capita energy consumption
- Full decarbonisation of energy occurs, causing global electricity consumption to reach 20MWh per person per year – double or triple the typical consumption of a developed country.
By mid-century, Earth will have a population of about ten billion people, and so we will need 200 billion MWh per year, which is much larger than current global consumption of 30 billion MWh per year.
Let’s further assume that solar does most of the heavy lifting for decarbonisation, with support from wind.
Solar’s current growth rate of 20% per year is easily fast enough to reach 80 Terawatts of installed capacity in 2050 – enough to decarbonise an affluent world. As well as eliminating most greenhouse emissions, we will also get rid of car exhausts, smokestacks, urban smog, coal mines, ash dumps, oil spills, oil-related warfare, and gas fracking. This sounds really good. But how realistic is this?
These climate conferences need to focus on opening up electricity markets. Getting rid of fossil fuels allows elimination of three quarters of global emissions through the substitution of electric machines for fossil fuel machines, with electricity coming from solar and wind.
Per capita electricity consumption
No constraints
There are practically no constraints on vast deployment of solar. Most of the global population will rapidly and hugely benefit from this energy transition.
Solar is cheap and getting cheaper. Solar’s dominance of global energy deployment (figure1) is compelling market-based evidence of this.
The sun will shine for billions more years. We can never run out of raw materials for solar panels. There are no toxic metals, no critical materials, and panels are highly recyclable. Storage is a solved problem via batteries and pumped hydro. We will never go to war over access to sun and wind. Solar technology has low utility for warfare and terrorists.
Most countries have vastly more solar and wind resources than needed to be energy self-sufficient which confers resilience in the face of war and pandemics. Densely populated regions such as Japan, Europe and northeast USA have enormous offshore wind, while Indonesia and west Africa have enormous offshore solar resources in calm tropical seas.
We have plenty of space. Eighty Terawatts of solar translates to 8 kilowatts (kW) per person. This is the size of a typical Australian rooftop solar system, albeit the system is shared by a family rather than an individual. However, it is not hard to imagine 8kW of solar per person by 2050, plus a 2kW share of a wind turbine or 12kW of solar and no wind.
The required area of a solar panel is about 5m2 per kW. Some of the panels will be on house roofs (which alienates no land). Others will be on ground-mounted solar trackers, in combination with agriculture, and floating on lakes and seas. These operate for 30 years and eliminate all fossil fuels from electricity, transport, heating, metals, chemicals, and jet fuel.
The solar revolution is clearly unprecedented: a cheap unlimited energy forever with minimal resource, environmental and social constraints. (Originally on www.powerengineeringint.com)