International Energy Workshop Venice, Juin Impacts of climate change on the energy systems with the POLES model Silvana Mima Patrick Criqui LEPII, CNRS-Université Grenoble 2

International Energy Workshop Venice, Juin Impacts of climate change on the energy systems with the POLES model 1. Impacts on energy consumption, heating and cooling demand in the residential and service sector 2. Impact of climate change on hydroelectricity production 3. Changes in water regimes and the costs of cooling in thermal power production (fossil or nuclear plants) 4. Changes in water regimes and energy consumption for water supply

International Energy Workshop Venice, Juin Introduction u POLES is a partial equilibrium model of the world energy system to 2100, with year by year simulation of supply, demand and price interactions u Population, GDP by region, Oil and Gas resources, are exogenous u Technology costs and performances of about 50 key energy technologies, either exogenous (TECHPOLdb) or endogenous with Two Factor Learning Curves u Simulation provides international and national energy prices, full energy balance for 47 regions and 13 final sectors, CO2 and other GHG emissions u Central role of prices and technological change, diversified energy scenarios through GHG abatement policies in a consistent economic framework (carbon tax or emission quotas) u Introduction of the impacts of climate change on the energy sector and to perform assessment of the adaptation costs u Limitations: no explicit macro-economic model and built-in feed-back.

International Energy Workshop Venice, Juin Impacts on energy consumption, heating and cooling demand in the residential and service sector u Studies have attempted to evaluate the impacts of climate change on energy consumption, particularly on heating and cooling in residential and/or commercial sectors u Changes in heating and cooling degree days, expected change in cooling market penetration, and related heating and cooling energy demands : -Isaac and vanVuuren (2008) that is particularly detailed, global in scope, and focused on the effects of climate change scenario up to McNeil and Letschert (2007) for the method proposed to model the impact of climate change on residential cooling demand. -Aebischer and Catenazzi (2007) analyze the effects of climate change on energy demand up to 2035 in the Swiss service sector and then extent the methodology for different climate zones in Europe. u The POLES energy demand module have been improved in order to represent the interactions between climate change, heating and cooling degree days with energy demand in the domestic and tertiary sector, by region

International Energy Workshop Venice, Juin Methodology : Heating u Based on estimates from literature, the final consumption for substitutable energy in the residential sector is split into two parts: the demand that is affected by climate change (thermal comfort, heating and cooling) and demand that is not (hot water, cooking) u The climate change impacts on heating demand in the Residential and Service sector is then based on heating degree days (HDD) provided by Timer/IMAGE for contrasted CC scenarios (2°C and 4°C, from the FP6 ADAM project)

International Energy Workshop Venice, Juin Methodology : Cooling u The method proposed to model the impact of climate change on residential cooling demand is based on the paper of McNeil and Letschert: -The air-conditioning equipment rate is the multiplication of the climate maximum saturation rate by the air-conditioning availability -Climate maximum saturation depends on the cooling degree days -Residential Air Conditioning Availability depends on revenues, following a logistic S-curve -The air-conditioning unit energy consumption depends on the cooling degree days, but also strongly on income (equation derived from Isaac,Van Vuuren, and from McNeil)

International Energy Workshop Venice, Juin Final consumption of substitutable energy for heating in the residential sector w/o and with CC in a 4°C scenario Increase in temperature clearly limits heating demand. The gap enlarges in time from -15 % by 2050 to -31% by 2100 at world level and from -17% to -35% for EU27 This translates into a reduction of total substitutable energy demand of -4% in 2050 and -6% in 2100 at world level, and respectively -10% and -15% in the EU27 level. Results in the service sector are comparable

International Energy Workshop Venice, Juin Final consumption of electricity in the residential sector w/o and with CC in a 4°C scenario Impacts on heating and cooling are significant when taken separately, with heating demand decreasing by 31% worldwide by 2100, and air conditioning demand increasing by 105% The net effect of climate change on global energy use and emissions is however limited, as the increases in cooling are compensated for by the decreases in heating, but the final fuel-mix is impacted

International Energy Workshop Venice, Juin Impact of climate change on hydroelectricity production u Changes in precipitations will impact hydrology in each world region and have an impact on hydro-energy production, while this primary source may be more solicited in a context of low-carbon energy policies u The driving force for the impacts on hydropower potentials corresponds to the discharge regime -- volume and timing -- of the rivers, which is mainly induced by changing precipitation patterns and evaporation: - precipitation changes may increase as well as decrease, depending on the region and season - while evaporation is expected to rise in most cases, due to higher temperatures u The hydro energy supply module will thus be adapted with a description of the interaction between climate change, water regimes and energy production, by main region

International Energy Workshop Venice, Juin Methodology u In order to take into account the future climate change impacts on hydroelectricity, we rely on information about changing hydro power potential available in the literature and the changes in the precipitations provided by IMAGE/TIMER model. u Two modifications of the POLES model must be underlined: -climate change impacts on available capacity factor for existing hydropower capacities which permits to calculate the impact in terms of hydro generation and -changes of the hydropower technical potentials on the construction of the new capacities. u We use the study realized by Lehner et al. (2005) with estimates of the impact of climate change on hydro power potential for Europe at a country level. Authors calculate the influence of climate change on the gross hydropower potential as well as its impact on the already developed hydropower capacity

International Energy Workshop Venice, Juin Impacts of climate change on hydroelectricity generation in a 4°C scenario u Preliminary results show an global increase of world hydro generation due to climate change of respectively 3.7% and 6.8%, in 2050 and u The impact varies from region to region: -hydroelectricity generation increases in the North America (7%, 12%), CIS (8%, 13%) and Japan & Australasia (7%, 6%) -while it decrease in Western Europe (-3.7%, -2.4%),

International Energy Workshop Venice, Juin Changes in water regimes and the costs of cooling in thermal power production (fossil / nuclear plants) u Analyses of changes in water regimes are also relevant for the identification of the potential impacts on thermal power production, either by fossil or nuclear fuels u These impacts will encompass limitations of production during extreme weather events and changes in the cooling technologies, with corresponding extra initial investment u Enhanced cooling technologies have to be included in the power generation module: direct cooling systems, cooling towers, moist and dry air cooling, etc. u Technological change and cooling choices - economic, environmental and performance tradeoffs: -Other new technologies (humid or dry air cooling for instance) ? -Moving the power plants to the coasts to use sea water ?

International Energy Workshop Venice, Juin CC and thermal power: preliminary results in a 4°C scenario (a) u Two types of results are considered: the impacts of CC on thermal electricity generation and on water withdrawals for cooling u Apparently the impacts seem limited, particularly until In 2100, world and EU27 thermal electricity generation is -8% and -7% % lower than in the case without a taking into account the impacts of higher temperature

International Energy Workshop Venice, Juin CC and thermal power: preliminary results in a 4°C scenario (b) u The decrease in the efficiency and availability of power plants modifies competition between technologies. At world level, Coal and nuclear are negatively impacted (respectively -7% and -19%), while gas-based generation increases (13%). Trends are similar in Europe.

International Energy Workshop Venice, Juin CC and thermal power: preliminary results in a 4°C scenario (c) u The decrease in thermal power is accompanied by a decrease in the water consumption for cooling u The adoption of new advanced cooling technologies require more information on their cost and performances which is under preparation in TECHPOLES database u Limited water availability and waste heat assimilative capacity can constrain the development of new thermoelectric generation. This is difficult to account for, as long as the competition between different uses of water is not considered

International Energy Workshop Venice, Juin Changes in water regimes and energy consumption for water supply u A new water demand module – GeoPol – is under construction, aiming to project water demand by sector in each region of the POLES model. u Data collection to provide the necessary inputs is also under preparation: -water consumption by sector and country -supply by main source, i.e. surface, underground, recycled and desalinated -water for energy and energy for water matrixes u Key water supply technologies will be detailed, in order to identify pumping, desalination, recycling, water transfers, and corresponding energy requirements

International Energy Workshop Venice, Juin A simplified demand model (a) u The “energy intensity profile” approach (P. Criqui, Ecodécision, 1992) has been used for the initial projection of regional consumptions of key materials in the POLES model ?

International Energy Workshop Venice, Juin A simplified demand model (b) Water withdrawal Intensity (m3/€) u A similar approach is used for the initial projection of water demand in GeoPol v.0

International Energy Workshop Venice, Juin Preliminary results : Water withdrawal intensity by region

International Energy Workshop Venice, Juin Preliminary results : Total water withdrawals The projected World and EU27 total water withdrawal with and without climate change up to 2100 show little impact on water withdraws for the first half of the century and an impact of around 8% for EU27 and 10% for the whole world at the end of the period

International Energy Workshop Venice, Juin Preliminary results : per capita water withdrawal Industrialized countries, although they reduce the withdrawal intensity, maintain a higher level of per capita withdrawal compared to developing countries

International Energy Workshop Venice, Juin Preliminary results : Electricity for water supply The pattern of electricity consumption for water supply follows similar trend as withdrawals This is explained by the fact that technological progress is largely compensated by deeper underground sources and farther distances

International Energy Workshop Venice, Juin Conclusions u The paper describes the first stages of a model-based approach for analyzing possible impacts of CC on energy systems at a country level. u Many uncertainties remain including the potential for extreme events that may threaten energy supply. This calls for further research for making the results robust an useable for policy makers u It is necessary to keep in mind too, the limits of a sectoral modeling approach. This may call for a future connection with other climate or hydrological models u The preliminary results suggest that expected changes in average temperature rise, or precipitation and hydrological regimes need to be accounted for future adaptation strategies in energy and water policies u Improvements in the near term will include: -Detailed water withdrawals by sector -Improvement in thermal electricity cooling technology database (TECHPOL) -Introduction of technology competition for the desalinization of water -More accurate simulation of the relationship between changes in precipitations and average temperature and water demand