Over the years all inland coal plants in the UK have switched from open to closed loop cooling, whilst gas plants are a mixture of both. Closed loop reduces environmental impacts as thermal discharge is to the air (instead of to water) and abstraction volumes are small, although consumptive losses are higher. Coastal power stations almost always use open loop cooling, but the effects of thermal pollution and fish entrainment and impingement on local ecology can be substantial (18).

When sufficient cooling functions are not possible, power station operators are required to ‘ramp down’ the generation output in order to reduce cooling demand, whether this is to maintain safe and efficient operation or to protect the aquatic environment according to legislative constraints on abstraction volumes and discharge temperatures (16).

A reduction of CO2 emissions by 80% by 2050, a legally binding target of the UK Climate Change Act 2008, may be reached through several pathways of different mixtures of energy sources (16). These pathways have impacts on the water resources. Pathways with high levels of nuclear and carbon capture and storage, for instance, show an increase of abstraction and consumption levels that far exceed current use. Carbon capture and storage technology, especially, significantly increases the intensity of freshwater consumption.  Significant reductions in freshwater consumption are possible through wide scale use of hybrid cooling, which would increase the level of freshwater resources available, for either the electricity sector or other uses. Hybrid cooling would however marginally increase cost and emissions, but also security of supply, by enabling the use of air-cooling during low flows when abstractions may be prohibited (16).

With high levels of nuclear, abstractions of tidal and seawater can be expected to increase substantially. The greater the need to protect inland water resources for agriculture and public water supply, whilst maintaining levels of environmental quality, the greater the pressure will be to shift thermoelectric generation towards the coast. In this case, careful management of the effects of fish entrainment and thermal pollution in marine and estuarine environments will be required (16).

Demand

West and Gawith (1) report on the energy sector in England. While there will be a reduction in the need for winter heating, the demand for summer cooling will increase. It has been estimated that the percentage change in cooling energy for air conditioned commercial buildings are over 10% by the 2050s and around 20% in the 2080s (2).

Increased temperature could change the demand for energy, with a reduction in demand for winter space heating and an increase in the demand for cooling in the summer. Reduction in winter space heating demand could help to reduce incidences of fuel poverty (3), although this will depend on future energy costs and housing conditions. Use of natural ventilation, shading, and green spaces for cooling may be able to meet any increased demand for cooling but these measures will need to be incorporated into building design.

Electricity network

Potential impacts of climate change on the UK’s electricity network have been assessed (13):

• Future projections of wind and gale faults indicate that they may remain the same, increase, or decrease in the future, due to uncertainty in wind gust projections;
• Lightning faults are projected to increase in the future as a consequence of a greater number of days projected with stronger convection;
• In the future snow, sleet and blizzard (SSB) faults are projected to decrease due to a reduction of snow days, but when snow does fall the intensity of the event may remain the same or increase;
• The incidence of solar heat faults is projected to increase throughout the UK, due to projected increases in maximum temperatures. However, due to the network’s resilience to high temperatures, these faults are likely to remain relatively rare;
• The occurrence of rainfall amounts that have caused significant flooding events in the past may increase in the future, but a decrease cannot be ruled out. However, this assessment has not explicitly considered important terrestrial processes.

During the floods of 2007 tens of thousands of people lost power. The ‘near-misses’ at Walham substation (serving 500,000 people in Gloucestershire and south Wales) and a number of electricity substations around Sheffield (servicing 750,000 people) that brought home the vulnerabilities of infrastructure assets. The failure of supply on that scale in either region would have caused chaos and, almost certainly, loss of life (15).

Hydropower

The primary vulnerabilities of the energy sector are associated with sea level rise, storm damage and intense precipitation events (4). This latter impact will, for example, lead to increased water levels and overflow volumes in reservoirs built to a design specification of a 1 in 10,000-year flood event. Rectifying this would require extensive improvement works on all reservoirs. Earlier snowmelt would also reduce the effectiveness of hydropower into late spring and early summer. Large-scale infrastructure will require a long lead-time to adapt to climate impacts. Customers will ultimately pay for the additional cost of climate impacts borne by industry.

Infrastructure

Analysis and experience has shown that energy infrastructure may be vulnerable to certain aspects of climate change; however the infrastructure has a significant degree of resilience to change, and therefore adaptation. In addition, technically it will be feasible to deal with adaptation issues over short, medium and long-term periods (11).

Oil platforms are designed to withstand 1:1000 year waves, which are of the order of 30 metres high. Wave heights close to this specification have occurred west of Shetland. Expert respondents suggested that by the 2050s the evolution of the industry is likely to mean platforms will be floating rather than attached to the sea floor. Such structures are less susceptible to wave damage. The general opinion received was that the physical impacts of climate change are not the major issue for the offshore industry (4).

Mining

In 1997 nuclear predominated with a 42% share of generation, followed by coal (~29%). Scottish mines are 'wet', in terms of the volume of water pumped per tonne of coal produced, and continuous pumping is required to extract coal. It is not known whether climate change, for example more intense rainfall events, will affect operations. The pollution control of abandoned mine water is of great importance, since the 1995 River Survey suggests it can have a devastating effect on surrounding receiving waters (4).

A blank cell indicates that no specific issues were identified for the region besides those noted in the first row. Each region identified and discussed issues differently, so this table might not provide comprehensive coverage of all issues.

Region Positive impact on energy Negative impact on energy Uncertain impact on energy Majority of regions Opportunities for biofuels and renewables Higher risk of damage to infrastructure Changes in seasonal demand South East       London       East of England       East Midlands       West Midlands Less fuel poverty. Reduced damage to infrastructure from freezing weather and ice Power stations constrained by water availability   Wales   Reduced performance of hydroelectric plants   North West   Distribution affected   North East   Disruption to supply through weather events. Additional cooling may be needed in industrial processes   Scotland       Northern Ireland Greater development of renewables. Efficiency gains  

Significant market opportunities exist for many business sectors to develop climate-proof products and services which reduce climate impacts and increase adaptability (2,6):

• The development and increased use of renewable energy products within this sector and others will result in increased demand for technologies such as solar power, heat exchange technologies and tidal power installations.
• The use of on-site renewable energy will also reduce dependency upon vulnerable energy distribution infrastructure, and reduce energy costs related to fossil fuel combustion.
• Groundwater heat pumps could utilise the cooler underground waters for cooling of buildings, whilst heat exchangers extending into the river Thames would moderate temperatures in summer, also providing some warmth in the winter.

In the United Kingdom 2°C warming by 2050 is estimated to decrease fossil fuel demand for winter space heating by 5 to 10 % and electricity demand by 1 to 3 % (7). On the other hand, in London the typical air conditioned office building is estimated to increase energy used for cooling by 10% by the 2050s, and around 20 % by the 2080s (8).