A solar energy revolution is brewing that will put the coal and nuclear industries out of business. Solar is already reaching price parity with coal in many parts of Australia. In contrast to coal and nuclear, solar is fully sustainable and safe. Solar is now an established industry that is growing very rapidly.

The CO₂ emissions from a modest four-star house with modern efficient appliances are about 6 tonnes per year. Emissions from a typical car driving 10,000 km per year are 1.5 tonnes per year. Installing a 5 kilowatt photovoltaic panel will fully offset these amounts of CO₂ by reducing the need to operate a coal fired power station.

We’re well on the way to grid parity

Photovoltaic power has reached retail grid parity for three out of four Australians – everywhere except Victoria, Tasmania and Canberra. Retail grid parity means that it’s cheaper to get electricity from photovoltaic panels on your house roof than to buy it from the grid.

In Adelaide, photovoltaic power is only two-thirds the price of retail grid electricity. By 2015, grid parity will be achieved in all of Australia, as well as in nearly every temperate country in the world – about 6 billion people.

Eliminating CO2 emissions from electricity production will be easier, cheaper and faster than most pundits predict. The faster that the solar energy industry develops, the less damage from greenhouse gas warming will occur.

Solar or clean coal?

At the moment, the only large scale energy sources are fossil, nuclear and solar energy (both photovoltaics and solar thermal). Other sources such as wind, hydro, biomass, geothermal and ocean energy can make large regional contributions, but cannot provide a global energy solution.

AFP Photo/Boris Horvat

Currently, electricity in Australia comes mostly from coal, which produces lots of greenhouse gas emissions. So called “clean coal” technology with carbon capture and storage doesn’t exist on a commercial scale. It will be much more expensive than dirty coal, and is in competition with falling solar power costs.

Solar and wind already dominate new generation technology in many countries. Indeed, it could be that no new coal fired power stations will ever be built in Australia.

Is nuclear an option?

It is difficult to see how the nuclear power industry will cope with falling solar prices and increased perceptions of risk following the Fukushima accident. Solar and wind power will soon put the nuclear power construction industry out of business.

Solar energy is vast, ubiquitous and indefinitely sustainable. There will never be a major solar accident, there’s minimal waste disposal issues, and we will never go to war over solar energy. Solar energy systems utilise only very common materials that we could never run out of and there’s minimal need for mining (about 1% of that needed for an equivalent fossil or nuclear power plant).

Australia receives 30,000 times more solar energy each year than all fossil fuel use combined. Australia’s electricity consumption could be met from roof-mounted photovoltaic panels. About 0.2% of the world’s land area would be required to provide all of the world’s electricity from solar – much of it on building roofs and in deserts.

Solar industry is booming

Worldwide solar sales are 100 times larger than in the year 2000, and the industry turnover now approaches one hundred billion dollars per year. In Australia, industry sales have grown from 10 megawatts in 2007 to 350 megawatts last year.

Sustained expansion is rapidly driving down costs – they have halved since 2007. Further large cost reductions are in train, through both technical innovation and mass-production learning curves.

It’s possible to estimate the cost of subsidising and accelerating solar technology to provide most of the world’s electricity. We add up the declining price difference year by year between solar and wholesale fossil energy, until it reaches zero. It would cost about a trillion dollars, spread over the next 20 years. That works out at $1 per week for each of the billion citizens of rich countries like Australia.

How do we store solar energy?

As the solar industry grows it will eventually be necessary to store energy. By far the largest energy storage today is pumped hydro - about three times larger than Australia’s entire electricity capacity.

During the day, water can be pumped up a 500 metre high hill with solar power, and released at night through a turbine to generate electricity. Pumped hydro doesn’t need to be located on a river, since the same water goes round and round a circle. Since storage is needed only for a day, the water store can be quite small.

The area of lake required to provide one day’s storage of Australia’s entire electricity production is 5 m2 per person. There are thousands of suitable sites in Australia.