Sir David King, a former UK government chief scientific adviser, and the respected economist Lord Richard Layard, are both proposing a worldwide Sunpower Programme to replace carbon fuels with solar energy in an article in the Observer online (29 Sept 2013). The aim of the programme would be to reach an economic tipping point in 2025 when the unit price of energy from solar becomes cheaper than from carbon fuel.
“The sun sends energy to the earth equal to about 5,000 times our total energy needs. It is inconceivable that we cannot collect enough of this energy for our needs, at a reasonable cost”, they are quoted as saying.
The article goes on to discuss how they acknowledge that a number of scientific breakthroughs will be needed to make cheap solar energy a global prospect. In particular, the report states, “scientists will have to find ways to reduce the cost of transmitting electricity from areas of high luminosity and low land value to the major population centres of the world. This will require new materials that are much better at conducting electricity, without loss of power, than present methods. This would be a major aim of the new solar energy programme.”
The premise is fundamentally right in two ways. Firstly, solar energy is our planet’s only sustainable source of energy, and along with consumption rebalancing, it will provide a sound way forward. Secondly, poorer countries and communities living nearer the world’s equator stand to gain economically from capturing and selling solar energy.
However, maybe masses of pylons heading north (or a breakthrough replacement for energy transmission the scientists envisage) is not the best business model.
We should also consider what hydrogen has to offer as a means of transporting rather than transmitting solar-sourced energy. The attractions include using fuel cells to generate electricity at the point of consumption, both static for buildings and mobile for vehicles. Consumed in cities, whether using fuel cells or otherwise, it produces only heat and water. Hydrogen can be generated by a number of small and large scale methods, including using microbes in sunlight as well as in passing electricity through water.
But when you look at the physics of hydrogen it can be pretty horrible to handle. It will corrode steel pipes, unlike fossil fuel gases. It has to be incredibly cold before it becomes a liquid. It is usually transported at ultra-high pressure. When it burns you cannot see the flame. And in an accidental release it tends to explode rather than gently burn.
Not good news, you might think. But perhaps this horrible-ness is a strength. It means that micro production and micro transportation will be needed, favouring small and independent suppliers above the big energy companies. Of course, monopolies will tend to form, but they will have physics working against them. Small, independent solar energy firms could create and pump hydrogen into portable canisters which can then be shipped directly to markets as required and returned empty to any producer for refilling. Refuelling a car would mean replacing a small canister, around 5kg, so large, dangerous tanks of high-pressure hydrogen at filling stations in urban areas are not needed. Early adopters will not need to wait for a vast network of filling stations to be built, they just keep a spare canister in the boot (trunk). Full canisters could be sold at existing petrol (gasoline) stations, hardware shops and supermarkets.
All this technology already exists. Innovation in the energy sector is not so much about new discoveries, inventions, processes. It is much more about new business models that make use of existing knowledge, becoming mainstream because economically or culturally their time has come. In 1761 the Bridgewater Canal was started, connected the centre of Manchester to a coal mine in Worsley and halving the price of energy in the city. This development of having boats of coal pulled by horses would have been understood by Julius Caesar. But the industrial revolution required it, so it happened then. Now is the time for solar energy, and we may have more tools in our box than we realise.