Drax power station

Keeping the lights on

Coal provides 40 per cent of the world’s electricity. Can we meet growing energy demand and still save the planet?

It goes against received wisdom, but a recent report has concluded that to keep pace with growing demand for energy we have no other choice than to continue burning fossil fuels. So how do we balance that against the need to slow down global warming?

‘Surviving the Storm’ presents the results of a 12-year study into climate change and global energy supplies by the Windsor Energy Group, which has the backing of major oil companies, so it’s hardly unbiased, but there’s no denying that global demand for energy is rising as populations grow and governments try to pull their people out of poverty through development.

Despite the steady growth in the amount of power coming from renewable energy sources, coal is still the predominant fossil fuel used to generate the world’s electricity. The use of coal is at its highest since the 1970s, with around 40 per cent of global electricity now being generated from it, and it’s not going to be toppled from that top spot any time soon. Forecasts predict that it will carry on growing at 1.8 per cent a year until 2040. China and India alone will account for 89 per cent of this growth.

With this continued reliance on coal, the World Coal Association (WCA) has called for more urgency around investment in clean coal technologies, stating: “Increasing the average efficiency of the global coal fleet from the current level of 33 per cent to 40 per cent can be done with off-the-shelf technology that is currently available. This would make a significant contribution to global efforts, saving around 2 gigatonnes of CO2 annually - roughly equivalent to India’s total annual emissions.”

The WCA argues that concerted action is needed to make sure that global demand for “affordable, reliable and secure forms of energy” can be met cleanly. It points out that in the run-up to December’s COP21 international climate-?change conference in Paris, “there is no evidence to suggest that mitigation action arising from any climate treaty will come close to achieving emissions reductions necessary to limit atmospheric concentration of CO2 to 450ppm.”
As developing and emerging economies continue to choose coal, WCA has put together a concept paper, ‘Platform for Accelerating Coal Efficiency’ (PACE), setting out how we can keep the lights on while trying to ensure we do it with the most efficient power stations that keep greenhouse gas emissions as low as possible.

Clean coal technologies

Currently, the average efficiency of coal-fired power plants is 33 per cent, which is a lot lower than the 45 per cent achieved by state-of-the-art plants and still significantly below the 40 per cent efficiency that ‘off-the-shelf’ technologies can deliver. Every one per cent increase of in coal-fired power plant efficiencies can reduce CO2 emissions by between two and three per cent, so what are these off-the-shelf technologies that could deliver these quick environmental improvements within a PACE framework?

Cleaner coal technologies such as high efficiency low emission (HELE) coal-fired power generation and carbon capture, use and storage (CCS) are already commercially available and WCA says that if they are deployed now they can reduce greenhouse gas emissions from the entire power sector by around 20 per cent.

The authors of the PACE concept declare that in order to accelerate deployment of HELE plants we need a new approach. The vision is that for countries that still want to invest in coal rather than renewables, the most efficient power plant technology possible should be deployed through international public/private partnerships. Governments and corporations would work with NGOs, think tanks and research institutes, at both local and international levels, to provide a supportive, knowledge-driven environment for increasing deployment of HELE technologies.

The long game

While it is not in doubt that the amount of carbon in our atmosphere can be cut by CCS projects, the questions that do have to be raised are whether carbon capture projects will mean we stop focusing efforts on those that deliver meaningful carbon emission reductions; and, perhaps more importantly, about what the long-term environmental impacts are going to be from pumping all this gas into pockets under the land and beneath the world’s oceans.

It seems that nobody wants to put their hand up and unequivocally admit that we don’t really know for sure. While leakage has been identified as the biggest risk, either as a slow drip leak or a big burst one, a 2005 Special Report on CCS produced by the Intergovernmental Panel on Climate Change (IPCC) suggests that the environmental risks associated with it are low and “…well-selected geological formations are likely to retain over 99 per cent of their storage over a period of 1,000 years.” It’s not very definite-sounding, is it? And it could seem that CCS has the potential to be just another example of short-term thinking, which is a trait of all our governments over the past few decades.

But several studies have been undertaken into what the long-term effects of CCS could be on the environment. One was the ECO2 Project, which was funded by the European Commission to develop a framework of best environmental practices to guide the management of offshore CCS projects in geological formations deep below the seabed. One focus was on the potential and actual impacts on marine ecosystems that could occur at CO2 injection facilities below the seabed and across entire storage sites if they leak. Early indications are that it could have the same kind of effects as ocean acidification but in a shorter time frame. So while some marine life such as molluscs could suffer, others like algae would thrive.

Another EU project was RISCS (Research into Impacts & Safety in CO2 Storage), which looked into the likely effects of leakage from CSS sites, both on and offshore. One focus of these studies was the potential consequences of leaks for humans, ecosystems and groundwater. Then there are also the results of the European Environment Agency’s technical report into CCS to take into account, which revealed that emissions of other pollutants, namely particulate matter, ammonia and nitrogen oxide, are expected to rise during the CCS process.

Mitigate or cut?

Over all, while it appears that CCS could help us to make great progress in achieving our goals of drastically cutting the carbon emitted into the atmosphere, it’s not actually helping much at all in cutting how much we emit in total, which is why many in the climate change mitigation field see it as a transitional technology rather than a viable long-term solution.

It seems that the long game definitely has to see us concentrating more efforts on becoming a truly low-carbon world rather than that just focusing on finding new places to store it.

Sign up to the E&T News e-mail to get great stories like this delivered to your inbox every day.

Recent articles