This is the fourth of six chapters in Eberhard Rhein’s Malta lecture series.
Humanity has the means to do without fossil energy. It will have to do so anyhow within the next 200 years or earlier because of the progressive depletion of fossil energy resources.
To do so will require a huge international effort improving/changing technologies and stepping up investments in more efficient and alternative energy technologies. The IEA estimates the annual investment necessary at $ 1 trillion until 2050, more than 10 times the volumes in 2007 and 2008. That will only be doable if national policy makers attribute the necessary priority to fighting climate change and set the appropriate instruments.
Let us look at the technological ways and means. In 2008, the IEA has published its Energy Technologies Report 2050, which assesses 17 main technologies that would help humanity reducing green house emissions by 50 percent below 1990 levels until 2050.
Half of the necessary reductions should be achieved by raising energy efficiency, the other half coming from the gradual transition towards alternative energy technologies that emit less or no green house gases.
Energy saving by behavioural changes
This is the simplest and cheapest method of reducing green house gas emissions.
Here are a few examples of how consumers can save energy without major investments or revolutionary technologies.
- Walking short distances,
- Using energy-efficient cars, household equipment etc.
- Using public transportation,
- Setting temperatures lower in winter and higher in summer,
- Switching all electric equipment when not used etc.
- Improving the thermal insulation of buildings with simple means.
- Avoid flying long distances.
This sort of energy saving has been one of the factors driving down energy consumption in post-communist countries after 1990, as a consequence of more adequate pricing and new awareness, without major investments in energy efficiency. Essentially it took place because energy prices went up dramatically from their abysmally low, heavily subsidised levels during the Communist era.
There is still a significant potential globally for this type of easy energy saving, especially in countries like USA, Russia, Ukraine, Gulf States with low energy prices and even subsidies on fossil energy consumption.
But there are evident limits to how far humanity can advance this way. It is therefore necessary to explore more efficacious methods, which require advanced technological means, some of which existing and others still to be developed or improved.
Raising energy efficiency
Energy efficiency is very low in most applications due to losses from the source (oil drilling, gas hole or coal mine) to the final user, e.g. electric engines in a factory or combustion engines of a car. Some of these losses are incompressible due to physical laws; but many can be reduced or eliminated by improvements or repair of the transmission lines/pipes, generating equipment etc.
As a rule of thumb three quarter of the energy is lost on the way “from the well to the wheel”.
- The most advanced European CHP (combined heat and power) coal-fired power plants cycle reach an energy efficiency of >80 percent, three times higher than outdated plants in China generating only electricity and not using the waste heat.
- Modern buildings with perfect thermal insulation need 10 times less heating or cooling energy than buildings constructed 40 years ago before the first oil crisis, when the price of oil was $ 3/b.
- Combining thermal insulation with active renewable heating/cooling devices like thermal pumps, solar PV, solar heating enables buildings to do without external energy, in optimal locations.
- Fuel efficiency of automobiles has been raised substantially in the last few years by design changes and new technologies (streamlining of bodies, weight, switch from gasoline to diesel, hybrid engines). It is possible to reduce the average gasoline consumption to 3-4 litre compared to 8 litres presently. To do so governments have to impose stricter mandatory efficiency standards.
- Modern LED light bulbs consume only a fraction of the conventional incandescent bulb. Lighting is accounts for a huge volume of global C02 emissions: the equivalent of 70 percent of those from the world’s light passenger vehicles. It therefore makes a lot of sense to phase out inefficient lighting, as the EU has decided most recently.
The examples are infinite in all fields where energy is consumed. One only has to look at the most effective companies, industries or countries to find out.
Investing in higher energy efficiency is the cheapest and fastest method for reducing C02 emissions. It reduces the demand for energy without impairing the well-being of citizens.
It would be much cheaper to refit European and American stock of buildings energetically than to build additional nuclear reactors, each of which costing more than € 3 billion.
For the coming 20 years, humanity should give priority to raising energy efficiency. This is of particular importance in the former communist countries and the oil producing countries.
But it takes incentives for business and citizens to develop and use technologies for raising energy efficiency. High fossil energy prices combined with mandatory standards constitute the speediest recipe for raising energy efficiency in the next two decades.
Applying and developing alternative energies
Whatever the potential for energy efficiency, humanity has no option but to develop technical alternatives, which one day, in less than 100 years should be able to supply humanity with enough energy for a decent life.
Most alternative technologies are still more expensive than conventional energy technologies. Thanks to large-scale production, e.g. wind turbines, energy-efficient electric lighting, and the cost advantages of conventional energy technologies will progressively shrink and disappear.
But it will take a long time to reach full competitiveness.
Governments therefore have to encourage the process by subsidising research efforts and making everybody pay the external costs of fossil energy. That is what forward looking governments in Europe, Japan and elsewhere have been doing during the last 30 years, by granting all sorts of subsidies. France has pursued the most determined policy by its resolute push towards nuclear power. So have Germany and Japan in the area of wind and solar PV.
Let us take a rapid overview.
The first drive into the non-fossil energy age started with the civilian utilisation of nuclear energy, back in the 1950s. The USA and EU were leading the movement. Europe created EURATOM in 1958! The oil shock accelerated the trend towards more nuclear energy. France developed it into the mainstay of its power supply. The USA undertook similar efforts. These came to dramatic halt after the nuclear accident in Chernobyl 1986. For 20 years hardly any new nuclear reactors were built. It took the global oil crisis after 2006 for a renaissance of nuclear power.
After 50 years of investment in nuclear power accounts for no more than 16 percent of global electricity demand. In 2007 440 nuclear power plants were in operation world-wide, with a total installed capacity of 370 GW and almost 100 another plants in the planning or construction phases.
The IEA estimates that nuclear power might supply up to 30 percent of electricity in 2050, some 6 percent of global energy demand. But this would be a maximum.
Nuclear power will not be the solution for humanity’s energy and climate problems. It is not the favourite option, but rather a solution of last resort, even if the nuclear lobby wants to convince us of its superb advantages. But it might make a significant contribution, as it is a mature technology which allows generating power at competitive prices with fossil sources. It should therefore no longer benefit from government subsidies.
But nuclear energy has its drawbacks:
- Its fuel can be diverted to military purposes.
- Fuel reserves are also limited. So the fuel needs to be reprocessed.
- We have no satisfactory solution for the long-term storage of nuclear waste. Only two countries have chosen sites for long-term waste storage, USA and Finland
- Private insurance against the risks of accident is next to impossible.
- Popular resistance remains strong.
Hydro power is presently the most important source of renewable and energy. It will remain important, provided climate change does not radically reduce the water supply and power generation remains compatible with agricultural production. Additional capacities exist in Asia, Africa and Latin America. But it will become increasingly difficult to exploit these, due to environmental concerns, as we have seen in China (Three Gorges). Its share of global electricity generation will go down to 10-15 percent by 2050, as other sources for power generation will come into the picture
It is the most competitive of all sources of renewable energies, the only one that operates without state aids. It is a safe technology, without any of the problems that nuclear power poses. It is therefore the ideal source to invest in during the next two decades.
Wind power has been used as a source of mechanical energy for hundreds of years, even more than water (milling, shipping).
The modern wind power age started in the late 1970`s in response to the first oil crisis. The first engines had tiny capacities of less than 0.5 MW. Since then technology has made huge strides in terms of size (>5 MW), costs (<€ 0.1/kwh) and reliability.
The globally installed wind power capacity has grown annually by more than 20 percent during the last two decades. Today, wind ranges third after biomass and hydro among renewable energy sources.
Global installed capacity exceeds 100 GW. Wind has become the predominant technology used for new power plants in Europe and the USA in 2008, (>40 percent of new power capacities). Still, it supplies only 1 percent of global electricity demand!
This shows the extremely long time needed before a new technology replaces traditional ones.
The earth is well endowed with wind, though unevenly distributed. It is possible to place turbines off-shore, where wind is blowing with more force and higher regularity. But this poses new technological challenges. Off-shore wind generation is therefore still in an infant stage. Norway, UK, Germany are the leaders.
A lot of R&D is still necessary, especially on power storage, grid integration and resource assessment in difficult terrains
The more wind power is generated, at different locations, with improved smart inter-connections, the more reliable it will become as a source of electric power, up to the point where it may be also supplying the “base charge”, jointly with nuclear power.
Despite the brilliant outlook for wind energy, IEA does not expect wind power to supply more than 10 percent of global electricity supply in 2050, with a global capacity of 2000 GW, of which one third might be off-shore. Jointly with biomass, hydro and increasingly solar it would constitute one of the pillars of the future power supply.
Solar power is the ultimate renewable form of energy. Wind, waves, biomass are only specific forms of solar power.
The amount or solar energy, which hits the earth every hour, is equal to the annual energy demand of humanity. But because of the low intensity and intermittency of solar radiation it is difficult and costly to exploit on a large scale. The large-scale exploitation of solar energy remains the most ambitious technological challenge for humanity in the 21st century.
Presently solar energy provides less than 1 percent of the world’s commercial energy! By 2050 that percentage might rise to 6-11 percent according to IEA projections.
Its cost is expected to fall dramatically until 2050, to 4-5 US cents/kWh in sunny areas, comparable to present fossil power costs. By then the cost of fossil energy will have gone up dramatically, due to climate policy and increasing scarcity of fossil resources. It is therefore likely that the use of solar power will advance much faster than projected by IEA.
We distinguish two forms: thermal and photovoltaic (heat vs. light). Both have made great technological advances since the 1970s when large-scale research started.
The simplest forms of solar thermal power are plastic tubes, usually mounted on a roof, used for the production of warm water in households, including heating. This technology has conquered countries like Israel, Greece, and Cyprus more than 10 years ago. It is a cheap technology, which fits on every roof and should be mandatory in all houses south of the Alps. Their contribution to the global energy supply will remain marginal.
A more sophisticated thermal device traps solar heat in huge mirrors for generating temperatures of > 300°, from which to produce steam and electricity, not different from a classic power plant, except that the process does not emit any C02!
This technology, called concentrated solar power (CSP) is able to generate both heat and electricity. Solar thermal power plants with capacities of > 0.3 GW have been operating successfully for some 20 years in California, where plans for additional capacities of up to 2 GW exist.
In addition, power plants using this technology are being built in Algeria, Australia, China, India, Morocco and Spain.
The Sahara could easily generate all MED and European power requirements at acceptable costs (<€ 0.1/kwh), including huge volumes of desalinated water necessary to provide the cities around the MED.
The USA would need an area of less than 200 km2 (half of Germany ) to cover all its electricity demand.
For Europe, solar thermal power from Africa would constitute a perfect complement to wind energy. Solar power would be fed into the grid during daytime; any excess could be stored (by salt solutions or in water pumped into up-hill reservoirs) for overnight supply or inadequate wind supply.
To use these complementarities, Europe will have to invest heavily into a modern continental grid, capable of transporting electricity over long distances at low cost. The USA is about to advance Europe with its planned 5000 km intelligent grid, linking the West with the huge potential for wind and solar energy and the energy-hungry East and Mid-West.
We are still at the very beginning of using Sahara solar power. Before using it at large scale, providing and receiving countries will have to lay the political and legal groundwork and build the necessary infrastructure. That will take at least another 10 years. But it is bound to come well before 2050.
European utilities shy away from investing in North Africa, essentially for political reasons. They have no trust in the governments and the governments there lack the vision and technological grasp to join hands with their European neighbours to engage in huge investment programmes for solar concentrated electricity, which European utilities would import through high voltage direct transmission lines.
According to the IEA, CSP installations might supply as much as 6 percent of global electricity demand in 2050.
Photovoltaic electricity is the ideal form for decentralised power generation.
Since the 1980s, it has conquered the market for off-grid electricity needs, from water pumps, to traffic lights, isolated buildings, satellites, defence installations and maritime devices.
Only when production costs declined and when PV systems in modern buildings were connected to the grid thanks to feed-in tariffs, did the technology become truly interesting.
Japan, Germany and the USA have been the front runner for PV. Japan and USA owe their role to their dominant position in chip and transistor manufacturing, which requires the same raw material, poly-form or crystalline silicium.
Despite the cost coming down from high levels, it has remained expensive until most recently.
But due to recent breakthroughs in technology – film PV – production costs have tumbled and make it possible to envisage large-scale generation of PV solar power generation. In 2008, 50 power plants with a total capacity of 1 GW have been built world-wide, 90 percent of which in Spain. This would have been unbelievable five years ago. It is result of technology leaps and attractive feed-in tariffs.
These developments explain the recent upward revision of estimates for the future.
The EIA estimates that the total output of cells/ modules might rise to 10 GW annually after 2010. Industry even forecast an annual output of 23 GW p.a. as of 2011. If these estimate are corroborated by facts, PV solar generation is about to beat all other forms of renewable energies from the next decade onwards.
This would be revolutionary for the future of solar PV as a source of generating electricity and the EIA would have to revise upwards its 2008 estimates for 2050, according to which PV might generate 6 percent of world electricity generation.
Solar PV and CSP have traditionally been considered as complementary. The first one is ideal for small-scale generation on house roofs, facades and small areas of land, close to the consumer. CSP will remain a large –scale power source, in arid or desert zones with high and constant solar irradiation, with the advantage of also generating heat for industrial processes, desalination or storage of electricity.
But since 2008 this may no longer be true. The biggest PV power plans have for the first time reached a capacity of 60 MW.
Biomass, essentially wood, has been used by man for thousands of years for cooking and heating, until it has been progressively replaced by coal from 1750 onwards.
Today we experience a renaissance of biomass in more sophisticated forms. We convert sugar, soybeans, cereals and vegetable oil into biogas and biofuel for heating and gasoline.
Brazil has started investing in biofuels three decades ago, and is today the most advanced country producing and using it, thanks to ideal conditions for vegetation and immense agricultural and forest areas. In Brazil, the extensive use of biofuels makes sense energetically and economically, but only if it abstains from converting tropical forest areas into land used for producing biomass, as it has done, as well as Indonesia and Malaysia, quite extensively.
In the moderate climate zones – USA, Eu- this is much less evident. The energetic yield is lower, sometimes even negative, when agricultural crops are converted into biomass for gasoline. This goes for rape seed, but also for soybeans and maize, depending on the specific conditions of fertility, inputs of fertiliser, manufacturing processes, distances etc.
Moreover, this practice has raised legitimate objections: the large-scale diversion of fertile land for the production of energy plants has contributed to the steep rise of food prices we have seen in 2007-08.
When oil-gas prices rise beyond certain thresholds, say $100/b, farmers will find it irresistible to divert part of their crops to energy uses. We cannot ignore this interaction. But governments should renounce offering subsidies for dual food-energy crops, as the USA has done.
Humanity has to return as much biomass as possible to the soil to prevent an increasing impoverishment of soils, loss of humus and desertification. It should be very cautious and fully respect the forest principle of sustainability to all forms of agriculture.
We witness the consequences of excessive use of biomass in certain developing countries, where people desperately cut off brushes for heating and allow animals to overgraze arid lands.
Research is therefore directed towards non-food plants grown on marginal land, natural waste, and one day algae from the seas. These so-called ligno-cellulose feed stocks will be the basis for the second generation biomass, which will become crucial for supplying shipping and air transport with the necessary fuels. The first essays of using biofuels as a substitute for kerosene have been successful. There is legitimate hope that by 2050 biofuels might become the major source of power in aviation.
The IEA is extremely upbeat about the future of biomass use. According its most optimistic scenario, biomass might supply close to a quarter to global energy demand in 2050! It would become the most important source of renewable energy! To reach that ambitious target, 15 billion tons of biomass would have to be harvested and processed annually, half from forest and crop residues, the other half from purpose-grown energy crops.
It would be used for the generation of gas, electricity and fuels for transport, including aviation. Roughly one quarter of the gasoline/diesel demand for transport might be supplied by biofuels in 2050, requiring up to 4 percent global arable land and pastures.
Geothermal power does not play a major role today. No more than 10 GW are presently installed world-wide, e.g. in Italy, Iceland. By 2050, the global capacity might rise to 200 GW. There is therefore not much we should expect from it for supplying humanity with clean power at the horizon of 2050.
There are other technologies on which research is being undertaken.
One is ocean energy, using tidal and wave power. One 0.3 GW tidal power plant is in operation (Normandy), another one of comparable size is under construction in Korea. The UK is preparing a feasibility study for a very big one in Wales, which might have a capacity up to 8.6 GW, able to supply 9 percent of UK electricity demand and to operate for 100 years or more.
The global prospects for substantial increase of tidal power look dim, due to limited locations and environmental concerns.
Wave energy is still in an experimental stage, with tiny capacities of a few MW being planned off the British and Portuguese coasts.
Most recently, the exploitation of sea currents has started. A German consortium will build a 1 MW pilot plant ready to generate power as of 2014.
The boldest of all is, of course, nuclear fusion (of hydrogen deuterium atoms) for which major countries have formed a consortium (ITER) and set aside a big amount (>$ 10 billion) of funding. The first pilot reactor is being built in southern France. Under most optimistic assumptions it will not be possible to generate any fusion electricity before 2050; and the undertaking may well prove to be too complex (e.g. generating the heat of 100 million centigrade for creating the gas plasma necessary to merge hydrogen atoms).
Renewable and nuclear energy alone may not suffice making global energy supply C02 free before the end of the century.
Moreover, some countries with huge fossil fuel reserves like Canada (oil sands, the second biggest oil reserves on earth after Saudi-Arabia), Russia, China, USA, Australia (coal) may be reluctant to renounce exploiting what they consider as a major source of wealth.
That is why in the past 10 years a lot of research has been invested in the capture and storage of carbon (CCS). This is a complex technology applicable to power plants and energy intensive industries. It is costly to capture carbon dioxide, liquefy and transport it over long distances to underground or under-see cavities where it can be stored safely for centuries.
Two small pilot projects function, some 40 more are in the planning or preparatory stage. It will take certainly until 2020 and beyond before this technology will be ready for large-scale application. But there is quasi-certitude that it will be applied. But the scale of deployment will depend on the pace at which renewable energy sources will become fully competitive.
· It will not be an easy march towards the post-fossil energy era. Humanity will have to focus much more on how to optimally organise the necessary transition.
· Time is of the essence. It will not be possible to achieve deep cuts of C02 emissions in a few years without strong political push,
· In the coming 20 years, the focus should be on enhancing energy efficiency and fully exploiting available renewable technologies like wind, hydro power and nuclear.
· Beyond 2030, carbon capture and storage (CCS) will have to join, especially in China, India, Russia and the USA. As of today, new coal-fired power plants should no longer be built, unless equipped for later refitting to CCS technology.
Eberhard Rhein 07.04.09Author : Eberhard Rhein