Cutting European greenhouse gas emissions by 80 per cent by mid-century is not only possible - it would cost less than doing nothing.
European greenhouse gas emissions can be cut by 80 per cent by 2050, according to a study by the European Climate Foundation, released in April 2010. This can be done with or without nuclear, and with or without carbon capture and storage (CCS). It will cost less than doing nothing, but it has to start pretty soon.
The European Climate Foundation (ECF) has presented a roadmap for a low-carbon Europe (EU-27, Norway and Switzerland), prepared by several consultants, such as Oxford Economics, the Dutch ECN and McKinsey, which has prepared similar scenarios for Vattenfall power company.
In order to cut emissions by 80 per cent, the power sector must cut its emissions by almost 100 per cent. A number of paths are investigated, summarised in the table.
Measures outside the power sector are:
- Energy efficiency improvement of 2 per cent per year.
- Full phase-out of fossil fuels in buildings.
- Full phase-out of fossil fuels for transport, to be replaced by decarbonised electricity and second generation biofuels.
- All other identified emission abatement measures are implemented, such as CCS in industry and afforestation.
|Coal/gas w/o CCS||49||0||0||0|
Table: Power mix scenarios for 2050 (per cent).
* The baseline scenario comes from the International Energy Agency’s (IEA) World Energy Outlook 2009.
The power sector is nevertheless the most important. The 100 per cent renewables scenario is deemed possible, but is less explored. The 80 per cent renewables scenario is summarised in the figure, so as to give some detail:
The coal retrofit CCS is an option limited to plants built “capture ready”. All other CCS is new-build. PV is photovoltaic solar cells. CSP is concentrating solar power, where water is heated to steam to produce electricity; the plants are assumed to have sufficient heat storage capacity for six hours production during night or shade. This means that it is not quite intermittent.
The 100 per cent renewable scenario is in fact the above plus some more geothermal plus imports of solar CSP from North Africa, which is what the Desertec project aims at, but without any nuclear or CCS.
The intermittency problem is manageable from a technical point of view, according to the ECF, but demands a lot of new power lines and back-up plants. For example the RE80 needs 270 gigawatts of backup plants compared to 120 gigawatts for the baseline.
The need for transmission (power lines) is daunting. The existing regional interconnections now amount to 34 GW, which admittedly is a mix of apples and oranges as they differ in length. But with the same measure, about 165 extra GW will be needed, almost five times as many power lines as today. Assuming demand-side reduction measures, this can be shaved to 125 GW.
This demand reduction (DR), or moving the time for when power is consumed within the day, is a critical issue. The underlying assumptions for the DR are that the electrification of heating includes local heat storage, and that the electrical vehicles’ charging cycle is managed.
These may be conservative assumptions; there may be considerably more ways to shave peaks, if the price signal is strong enough.
The four issues of DR, new power lines, electricity storage and need for backup power are linked. The ECF assumes no electrical storage other than existing pumping hydro (running hydropower backwards some of the time, to provide extra capacity when needed) and some storage at solar CSP plants. The more DR there is, the less need for backup, storage and power lines, which can save tremendous amounts of money, and time. Some of the new power lines are solely needed to transport the electricity from, for example, offshore wind in the North Sea to big cities on the continent and in England. But some of the extra power lines are there to handle variations in supply, and these can be cut by more DR, which is much cheaper.
New backup power is also expensive, but it is a conservative assumption that of the existing hydro, only pumped storage can be used for storing power. At present, the regular hydropower dams act as electricity reservoirs and could be used more so, especially if nuclear power is phased out. Nuclear power is intermittent in another fashion than renewables, but when a reactor scrams, it goes unpredictably from full power to zero in seconds, which never happens with wind power. This was why the pumped storage facilities were built in the first place. These and other flexible supplies can be used to balance renewables; but they can’t do both.
With a large wind power component, there can be too much wind power. This can be dealt with by idling some wind capacity some of the time. This seems a waste, but it does not need to be very big. In the RE80 this “curtailment” loss of renewable electricity is 2–3 per cent.
Figure: Power sector mix in scenario RE80 (per cent). Solar PV = photovoltaic. CSP = Concentrating solar power. For further explanations, see text.
The study shows that a combination of solar and wind is more stable than wind alone. Biopower is both stable and can balance wind. Geothermal is stable, but cannot balance.
The ECF scenarios assume no wave power. This again may be conservative. If wave power can be mastered, the potential is huge, and the load is both smoother, more predictable, and not in phase with wind power; when the wind slows, the wave height falls several hours later.
In short, a high penetration of intermittent renewables may present a big problem. But that big problem can be salamied into a number of more manageable slices!
In the baseline scenario, the power demand is assumed to increase 40 per cent over the 40 years up to 2050. From that level, ECF cuts back by 30 per cent through efficiency gains but then again adds back about the same amount due to electric transport, heat pumps for heating and cooling and some increased use in industry.
This all-big, all-electric vision is not what all environmentalists wish for, but it does show that there are choices to be made, and that the do-nothing option is in many respects the worst.
The cost exercises show that there is not a very big difference between the choices, though a large share of renewables means high capital costs early on, and then lower costs for operation and maintenance later, while keeping fossil fuels will be ever more expensive. Compared to the baseline, the decarbonised path decreases energy costs 9 per cent by 2020 and 25 per cent by 2050 – assuming an oil price of only $115 by 2050.
Acording to the study, the short-term implications for achieving its objectives are, for example:
- Establish a framework for EU-wide solutions, especially for interregional grid planning.
- Ensure adequate incentives and funding for the required investments, including early success in energy efficiency.
- Sound a loud and clear message to the market that decarbonisation will take place, and that investments ignoring this message will be risky.
- Develop commercial-scale biomass fuel supply.
- Ensure massive investments in new low-carbon power stations, and gas infrastructure for backup power.
- Development of hydrogen infrastructure.
- Develop heat pumps and thermal storage systems, smart grids that allow demand response (DR) and networked high-voltage transmission technologies.
- Develop functioning CCS systems.
As for jobs, decarbonisation creates many more jobs than are lost in the fossil sector, but the ECF states that “short-term interventions could ensure that employees in vulnerable industries and regions are appropriately supported, both in financial assistance and in skills retraining, in the transition years 2010–2020.”