Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Effects of global warming on human health wikipedia , lookup
Surveys of scientists' views on climate change wikipedia , lookup
Fossil fuel phase-out wikipedia , lookup
Years of Living Dangerously wikipedia , lookup
Climate change and poverty wikipedia , lookup
Climate change, industry and society wikipedia , lookup
Instrumental temperature record wikipedia , lookup
IPCC Fourth Assessment Report wikipedia , lookup
Mitigation of global warming in Australia wikipedia , lookup
CLIMATE CHANGE—THE ACHILLES HEEL OF THE THERMAL POWER INDUSTRY Kristin Linnerud, CICERO, +47 94873338, [email protected] Torben K. Mideksa, CICERO, +47 22858562, [email protected] Gunnar S. Eskeland, NHH, +47 55959699, [email protected] Overview A warmer climate will result in lower thermal efficiency and more frequent shutdowns of thermal power plants. To identify these two supply-side effects we estimate regression models on nuclear plant capacity utilization data. We use different data sets and estimation strategies to control for other factors which are related with temperature and which may affect capacity utilization. Our results indicate that a rise in temperature of 1 degree Celsius reduces thermal power capacity with 0.1-0.5 percent through its effect on thermal efficiency; during droughts and heat waves the capacity loss increases to 1.0-2.0 percent per degree Celsius as the operation of cooling systems is constrained by physical laws, regulation or access to cooling water. Thus, more frequent droughts and heat waves may in the future pose a threath to energy supply security. Methods A rise in temperature may influence the capacity utilization of thermal power plants in two ways: I. Reduced efficiency: Increased environmental temperature reduces how efficient a thermal power plant is in turning fuel into electricity; i.e. the ratio of electricity produced to the amount of fuel used in producing it. II. Reduced load: For high environmental temperatures thermal power plant’s operation will be limited by a maximum possible condenser pressure. The operation of plants with river or sea cooling will in addition be limited by a regulated maximum allowable temperature for the return water or by reduced access to water. The 4th Assessment report of the IPCC reports that “Climate change could have a negative impact on thermal power production since the availability of cooling water may be reduced ...” However, while several contributions 1 identify these climate change impacts, few have tried to quantify them. Durmayaz and Sogut (2006) design a theoretical model for a pressurized-water reactor nuclear-power. They find that an increase in temperature with 1 oC of the coolant extracted from environment will yield a decrease of 0.12 percentage points in efficiency and a 0.45 percent reduction in power output. Daycock et al. (2004) measure the actual decrease in efficiencies on gas power plants located in a desert and their results are consistent with a 0.09-0.23 percentage point decrease in efficiency and a 0.55-0.73 percent decrease in power output for an increase of 1oC. Maulbetsch and DiFilippo (2006) address the need for alternative cooling systems as a changing climate makes water use and conservation at thermal power plants more important. They demonstrate that these water saving comes at a price including increased capital and operating costs, reduced thermal efficiency and reduced output. In this paper, we take the challenge of quantifying the impact of changes in climate on the supply of thermal power. More specifically, we estimate a regression model in which variations in thermal power plants’ capacity utilization is explained by variations in environmental temperature. The model specification and the estimation strategy are chosen so as to isolate the above mentioned two supply-side impacts: (I) reduced efficiency and (II) reduced load. The major problem is to control for other factors which are related to temperature and which also influence the thermal power plant’s capacity utilization. These factors are: 1) choice of technology which may reflect climate conditions, 2) planned maintenance which is normally laid to the summer months and 3) seasonal changes in demand. 1 See e.g. Arnell et al. (2005) and Bull et al (2007). To control for these factors we use two different datasets: a plant specific dataset and a panel dataset with aggregated observations for seven countries. In both datasets nuclear power plants are chosen as our object of study since nuclear power plants’ low marginal costs and low operating flexibility make their production less sensitive to temperature-induced demand shifts compared to other thermal power plants. Results Our plant specific estimation shows that a rise in environment temperature of 1 degrees Celsius will reduce output with 0.1-0.2 percent due to a fall in efficiency and, for high temperatures, with 0.9-1.1 percent due to both reduced efficiency and reduced load. Estimations on the panel data suggest an even higher temperature sensitivity of supply in general; a rise of 1 degree Celsius will reduce output with 0.5-1.0 percent for temperatures around 0 degree Celsius and 1.5-2.0 percent for temperatures around 15 degree Celsius. Conclusions These impacts may seem small. But, since 81 percent of all power worldwide is produced by conventional thermal power and nuclear power plants, it is important to take them into consideration when estimating expected costs of climate change. The net electricity generation from conventional thermal power and nuclear power plants was about 1,500 TWh in 2006 (EIA, 2008). A reduction in production capacity of 1-2 percent due to an increase in environment temperature of 2 degree Celsius would represent a drop of up to 30 TWh that might need to be replaced somewhere. This translates into the full production of 3 nuclear power plants with 1200 MW installed capacity. But, perhaps more importantly, more frequent droughts and heat waves may, by causing partial or full shutdowns of power plants, pose an energy supply security risk in the future. This points in the direction of investing in more robust cooling technologies and/or in more spare production and network capacity. Climate considerations will also become even more important when deciding where to build new thermal power plants. References Arnell, N., E. Tomkins, N. Adger and K. Delaney, 2005: Vulnerability to Abrupt Climate Change in Europe. ESRC/ Tyndall Centre Technical Report No 20, Tyndall Centre for Climate Change Research, University of East Anglia, Norwich. Bull, S. R., D. E. Bilello, J, Ekmann, M. J. Sale, and D. K. Schmalzer, 2007: Effects of Climate change on energy production and distribution in the United States in Effects of Climate Change on Energy Production and Use in the United States. A Report by the U.S. Climate Change Science Program and the subcommittee on Global change Research. Washington, DC. Daycock, C., R. Jardins and S. Fennel (2004). Generation Cost Forecasting Using On-Line Thermodynamic Models. Proceedings of Electric Power, March 30-April 1, 2004, Baltimore, MD. Durmayaz, A. and O.S. Sogut (2006). Influence of Cooling Water Temperature on the Efficiency of a Pressurized Water Reactor Nuclear-Power Plant. International Journal of Energy Research, 30, 799-810. EIA (2006). Annual Energy Outlook 2006,with projections to 2030. DOE/EIA-0383(2006). Washington, DC: Energy Information Administration. Maulbetsch, J.S. and M.N. DiFilippo (2006). Cost and Value of Water Use at Combined Cycle Power Plants, Calefornia Energy Commission, PIER Energy-Related Environmental Research , CEC-500-2006-034, April 2006.