Monthly Archives: February 2017

Solar Buses in China

Solar powered buses

Chinese Battery Electric Buses, with solar panels.

Over the years I’ve posted a number of blogs about why I’m optimistic that Chinese carbon emissions will plummet over the coming decade, and that the Chinese will make significant headway on tackling their ghastly air pollution. I’ve also written about lots of prototype zero emission transportation systems, but much less about the mass roll out of such systems and the effect they might have in reducing pollution.

Diesel buses and trucks are a major source of pollution in Chinese cities. Their days are numbered. Battery electric bus sales are booming. China represents 98% of the global market for such vehicles.  Many now have solar panels built into the roofs, as the above photograph shows. In Europe and North America a few pioneering places are doing small scale trials, mainly by importing electric buses from China. A few ground breaking efforts are being made to design and build electric buses, some with roof mounted solar panels, such as in Kampala, Uganda, by Makerere University and Kiira Motors, the first such project in Africa. However it is only in China that the rapid adoption of electric buses is forging ahead at incredible speed. The huge city of Shenzhen plans to have a fleet of 15,000 electric buses up and running by the end of this year. Other cities are expected to follow in rapid succession. There are several Chinese electric bus companies that are expanding very rapidly, such as BYD which is currently growing 50% per year. Chinese deployment of solar power is currently growing at 100% per year. Increasingly renewable electricity will be what fuels both the Chinese electricity grid and its public transport systems. Trains, trams, trucks, cars and motorbikes are all likely to go electric, or hydrogen fuel cell. It is now becoming possible to envisage fossil fuelled powered cars, trucks and buses in the same way we see steam trains, with a strange confused nostalgia for a more polluted past. If humanity is to have a future it will be with clean, pollution minimizing technology, and currently China is forging ahead of the rest of the world. Chinese carbon emissions rocketed during the decade 2002 to 2012 then levelled off for the last five years and now, I believe, are on the cusp of rapid reduction. And as carbon emissions fall so too will local air pollution. There is a long way to go, but improvements can be remarkably rapid, as the roll out of battery electric buses and solar power in China show.

China: CSP

China_provinces

The Provinces of China. New CSP will mainly be in Qinghai, Gansu & Inner Mongolia.

Concentrating Solar Power (CSP) uses mirrors and lenses to focus the energy of the sun to make steam, drive turbines and so make electricity. This solar technology can be used to directly drive industrial processes, desalinate seawater, or to power air conditioning via absorption chillers. With CSP heat is usually stored in molten salt and this is then used to generate electricity in the evenings after the sun has set. This is a very important advantage over photovoltaic solar. I’ve long been a fan of this technology and have written about it frequently on this blog. In the first decade of this century Spain lead the world, before abandoning support under the Rajoy government in 2010. In February 2013 I posted a blog asking ‘where next for CSP?’ I’ve posted blogs about Morocco, Chile, South Africa and USA who have all built impressive examples of this technology.

Until recently China had not built any serious CSP power projects. A couple of months ago they simultaneously announced twenty projects, ranging in scale between 50MW and 135MW, all with thermal storage and all designed and built mainly by local companies. Various mirror configurations will be used: parabolic troughs, power towers and Fresnel systems. All the projects will have to be up and running before 2019 to get the agreed price of 1.15 yuan/kWh. This is a very tight time scale, but I’d expect all will be achieved on schedule. The Chinese government refers to these as demonstration projects. If they are successful, which I’m sure they will be, I would expect the next tranche of projects to be on a larger scale. The projects are all in the sunnier west of China: mainly in Qinghai, Gansu and in Inner Mongolia. High voltage direct current power-lines will connect them to the cities on China’s less sunny east coast.

Jeremy Williams wrote an interesting blog about China’s carbon emissions and the various viewpoints people have about their future emissions. On this issue I’m firmly on the side of the optimists. I’ve blogged before about how China’s carbon emissions skyrocketed in the decade 2002 to 2012. They’ve since declined a little. I both hope and expect they’ll plummet over the coming decade, 2017 to 2017. Urban air quality is a very serious health issue in China, and China is also very vulnerable to climate change. The government is very conscious of these threats and has the money and technological ability to take action on a heroic scale and by doing so it will become a leader in both the technological and political spheres, just as USA is abandoning any sense of political leadership, particularly on Climate Change. China is investing heavily in most forms of low carbon energy, including nuclear, wind, solar photovoltaics and hydro. All forms of energy generation have advantages and disadvantages, but CSP seems to me to be one of the best for the hot dry regions of the world. These initial twenty projects will probably be followed by many larger scale projects over the coming decade, and make a significant and worthwhile contribution to reducing carbon emissions and local air pollution.

Solar pv: Exponential Growth!

Freiburg, Germany. An early solar pioneer

Freiburg, Germany. An early solar pioneer

I’ve just finished reading ‘The Switch’ by Chris Goodall about how solar photovoltaics will become the dominant source of global electricity production. The key point Goodall stresses throughout the book is the effect of the learning curve and how this has been bringing down prices by about 20% every two years and how total installed capacity has doubled every two years. This exponential trend has been going on for decades, but back in the 1970s and 1980s the biannual doubling was from a few kilowatts to a few more kilowatts, then a few megawatts to a few more, so generally photovoltaics were considered insignificant by mainstream commentators. Solar enthusiasts were an easily dismissed fringe group.

This exponential rate of growth has continued. In the last few weeks the global installed capacity of photovoltaic panels passed the 300 GigaWatt milestone. A couple more doublings and we will pass the TeraWatt level. Of course exponential growth on a finite planet cannot go on forever. However it does look as if solar power will keep expanding extremely rapidly for the foreseeable future, whatever politicians like Trump and Putin might do to try and stop it. There are a number of technical innovations in the pipeline that make continuing falls in production costs inevitable, and then simple economics means that rates of deployment will continue to increase.

Over the last two years China and Japan have lead the world. Globally about 1.2 billion people are not connected to mains electricity and at least another billion experience frequent power cuts due to poor grid infrastructure. Most of these people live in Africa and South Asia and it is in these regions that I would expect solar to grow most quickly over the coming decade. For the rural off grid tropics solar plus batteries is already cheaper than either diesel generators or connecting up to distant electricity grids. They will leapfrog the need for grids.

This week I was talking to someone in Herefordshire who is renovating a cottage and putting sufficient solar panels to run his air source heat pump and all his family’s electricity needs for most of the year. Smart technology will determine when appliances operate and when to store electricity for later use. An electric car could easily be added to the mix. Although still connected to the grid he envisages buying and selling as little electricity as possible. If half hourly metering comes in it will become profitable for him and useful for the grid managers, for him to buy electricity at times of weak demand and sell it at times of peak demand. In his renovation insulation and air tightness have been improved to minimize winter heating requirements. Globally such possibilities are opening up as the technology evolves. Within a decade I think it probable that hundreds of millions, or indeed billions, of households will operate in this manner. In the process they will make coal, gas, oil and nuclear power obsolete.

In colder cloudier climates wind, tidal and geothermal energy will undoubtedly have a major role to play. Batteries will be important for short term energy storage. There are an increasing number of emergent technologies focusing on interseasonal energy storage, such as renewable liquid fuels and gases, many of which will be created with surplus summer solar energy.

Solar still has a long way to go to become the dominant energy source, but if exponential rates of growth continue this might become the reality far faster than most people expect. Last year China more than doubled its solar capacity in a single year. Many other countries will more than double their solar capacity over the next year or two, and I’ll write about the most exciting examples on this blog. The Solar Age is coming.