Heating and cooling energy demand and related emissions of the German residential building stock under climate change

The housing sector is a major consumer of energy. Studies on the future energy demand under climate change which also take into account future changes of the building stock, renovation measures and heating systems are still lacking. We provide the first analysis of the combined effect of these four influencing factors on the future energy demand for room conditioning of residential buildings and resulting greenhouse gas (GHG) emissions in Germany until 2060. We show that the heating energy demand will decrease substantially in the future. This shift will mainly depend on the number of renovated buildings and climate change scenarios and only slightly on demographic changes. The future cooling energy demand will remain low in the future unless the amount of air conditioners strongly increases. As a strong change in the German energy mix is not expected, the future GHG emissions caused by heating will mainly depend on the energy demand for future heating.     

Modelling the effects of climate change on the energy system—A case study of Norway

The overall objective of this work is to identify the effects of climate change on the Norwegian energy system towards 2050. Changes in the future wind- and hydro-power resource potential, and changes in the heating and cooling demand are analysed to map the effects of climate change. The impact of climate change is evaluated with an energy system model, the MARKAL Norway model, to analyse the future cost optimal energy system. Ten climate experiments, based on five different global models and six emission scenarios, are used to cover the range of possible future climate scenarios and of these three experiments are used for detailed analyses. This study indicate that in Norway, climate change will reduce the heating demand, increase the cooling demand, have a limited impact on the wind power potential, and increase the hydro-power potential. The reduction of heating demand will be significantly higher than the increase of cooling demand, and thus the possible total direct consequence of climate change will be reduced energy system costs and lower electricity production costs. The investments in offshore wind and tidal power will be reduced and electric based vehicles will be profitable earlier.     

Dynamic temperature dependence patterns in future energy demand models in the context of climate change

Energy demand depends on outdoor temperature in a ‘u’ shaped fashion. Various studies have used this temperature dependence to investigate the effects of climate change on energy demand. Such studies contain implicit or explicit assumptions to describe expected socio-economic changes that may affect future energy demand.This paper critically analyzes these implicit or explicit assumptions and their possible effect on the studies' outcomes. First we analyze the interaction between the socio-economic structure and the temperature dependence pattern (TDP) of energy demand. We find that socio-economic changes may alter the TDP in various ways. Next we investigate how current studies manage these dynamics in socio-economic structure. We find that many studies systematically misrepresent the possible effect of socio-economic changes on the TDP of energy demand. Finally, we assess the consequences of these misrepresentations in an energy demand model based on temperature dependence and climate scenarios. Our model results indicate that expected socio-economic dynamics generally lead to an underestimation of future energy demand in models that misrepresent such dynamics. We conclude that future energy demand models should improve the incorporation of socio-economic dynamics. We propose dynamically modeling several key parameters and using direct meteorological data instead of degree days.     

Modeling global residential sector energy demand for heating and air conditioning in the context of climate change

In this article, we assess the potential development of energy use for future residential heating and air conditioning in the context of climate change. In a reference scenario, global energy demand for heating is projected to increase until 2030 and then stabilize. In contrast, energy demand for air conditioning is projected to increase rapidly over the whole 2000–2100 period, mostly driven by income growth. The associated CO₂ emissions for both heating and cooling increase from 0.8 Gt C in 2000 to 2.2 Gt C in 2100, i.e. about 12% of total CO₂ emissions from energy use (the strongest increase occurs in Asia). The net effect of climate change on global energy use and emissions is relatively small as decreases in heating are compensated for by increases in cooling. However, impacts on heating and cooling individually are considerable in this scenario, with heating energy demand decreased by 34% worldwide by 2100 as a result of climate change, and air-conditioning energy demand increased by 72%. At the regional scale considerable impacts can be seen, particularly in South Asia, where energy demand for residential air conditioning could increase by around 50% due to climate change, compared with the situation without climate change.     

Review of climate change issues: A forcing function perspective in agricultural and energy innovation

Climate change is observed globally, and the projections predict that the change will continue in the future for quite a long time. The mitigation and adaptation to climate change, however, are offering tremendous business opportunities around the world, especially for businesses operating in the agri‐food, energy, finance, and health sectors, water infrastructure, built environments, and other relevant services. When the severity of heat waves is considered, for instance, it would become quite clear that the demand for cooling would accelerate, putting further stress on energy supply and increasing the risk of electricity black outs. Similarly, the projections also provide warnings about increased drought risk in many regions around the globe, and even worse, it should also be emphasized that 60% more food will be needed globally, while 100% more demand for food is projected in developing countries by the year 2050. While all these are being projected, we are experiencing progressively increasing stress on our global freshwater resources, which are worsened further by climate change‐driven impacts and water pollution. Consequently, reducing agri‐food production systems' susceptibility to climate change and strengthening the resilience of such systems are extremely important to sustain and improve the livelihoods of billions of people around the globe. Moreover, reducing emissions due to fossil fuels consumption and production is vital for the whole global population, and agri‐food and energy sectors have tremendous potentials for reducing inefficiencies and emissions while simultaneously playing their crucial roles in food and energy security as well as poverty reduction. Both of these sectors are facing significant climate change‐driven challenges, which provide ample opportunities for cutting‐edge novel knowledge and innovative products, processes, services, and policies. And due to the reciprocal relationships between climate change and agri‐food and energy innovations, in return, complementing the other forms, such innovations will speed up the climate change mitigation and adaptation processes.     

Shale gas: A solution for energy crisis and lower CO2 emission in Pakistan

Energy supply is an essential element for development in any country. However, the huge energy demand in future, which depends mainly on fossil fuels, may create an environmental crisis. In this paper, an attempt was made to highlight the shale gas prospect of Pakistan as a solution for its future energy demands. It seems that Pakistan is currently consuming a huge amount of domestic natural gas and crude oil, which may soon result in climate change. As such, it is crucial to consider shale gas reserves as an ultimate solution for energy and achieving a low carbon economy.     

Vulnerability of wind power resources to climate change in the continental United States

Renewable energy resources will play a key role in meeting the world's energy demand over the coming decades. Unfortunately, these resources are all susceptible to variations in climate, and hence vulnerable to climate change. Recent findings in the atmospheric science literature suggest that the impacts of greenhouse gas induced warming are likely to significantly alter climate patterns in the future. In this paper we investigate the potential impacts of climate change on wind speeds and hence on wind power, across the continental US. General Circulation Model output from the Canadian Climate Center and the Hadley Center were used to provide a range of possible variations in seasonal mean wind magnitude. These projections were used to investigate the vulnerability of current and potential wind power generation regions. The models were generally consistent in predicting that the US will see reduced wind speeds of 1.0 to 3.2% in the next 50 years, and 1.4 to 4.5% over the next 100 years. In both cases the Canadian model predicted larger decreases in wind speeds. At regional scales the two models showed some similarities in early years of simulations (e.g. 2050), but diverged significantly in their predictions for 2100. Hence, there is still a great deal of uncertainty regarding how wind fields will change in the future. Nevertheless, the two models investigated here are used as possible scenarios for use in investigating regional wind power vulnerabilities, and point to the need to consider climate variability and long term climate change in citing wind power facilities.     

Driving forces and barriers in the development and implementation of coal-to-liquids (CtL) technologies in Germany

Because of a growing global energy demand and rising oil prices coal-abundant nations, such as China and the United States, are pursuing the application of technologies which could replace crude oil imports by converting coal to synthetic hydrocarbon fuels—so-called coal-to-liquids (CtL) technologies. The case of CtL is well suited to analyse techno-economic, resources-related, policy-driven and actor-related parameters, which are affecting the market prospects of a technology that eases energy security constraints but is hardly compatible with a progressive climate policy. This paper concentrates on Germany as an example—the European Union (EU)'s largest member state with considerable coal reserves. It shows that in Germany and the EU, CtL is facing rather unfavourable market conditions as high costs and ambitious climate targets offset its energy security advantage.     

Recent estimates of energy efficiency potential in the USA

Understanding the potential for reducing energy demand through increased end-use energy efficiency can inform energy and climate policy decisions. However, if potential estimates are vastly different, they engender controversial debates, clouding the usefulness of energy efficiency in shaping a clean energy future. A substantive question thus arises: is there a general consensus on the potential estimates? To answer this question, this paper reviews recent studies of US national and regional energy efficiency potential in buildings and industry. Although these studies are based on differing assumptions, methods, and data, they suggest technically possible reductions of ~25–40 % in electricity demand and ~30 % in natural gas demand in 2020 and economic reductions of ~10–25 % in electricity demand and ~20 % in natural gas demand in 2020. These estimates imply that electricity growth from 2009 to 2020 ranges from turning US electricity demand growth negative, to reducing it to a growth rate of ~0.3 %/year (compared to ~1 % baseline growth).     

The effects of changes in the climate on the energy demands of buildings

It is generally accepted that climate changes will have a major effect on our lives. However, buildings will also be faced with climate changes, and these changes will have an impact on indoor comfort, energy demands and the efficiency of building services, especially on those supporting free cooling and free heating. In order to predict the expected changes in a building's thermal response during its lifetime, it is necessary to look at the climate changes predicted for the future. In our study, the climate changes were considered by using simplified mathematical models combined with available test reference years to establish ‘corrected test reference years’. A transient simulation tool, TRNSYS, was used to simulate the indoor climate and the useful energy demand for the heating and cooling of different buildings with different free‐cooling techniques. In order to predict the expected changes in a building's thermal response, the meteorological parameters for the moderate, continental climate region of Slovenia were taken into account. The study shows that during a building's lifetime, significant changes in useful energy demands can be expected—a decrease in the useful energy demand for heating of between 23 and 40% and an up‐to‐38‐times increase in the useful energy needed for mechanical cooling. In buildings without mechanical cooling, the efficiency of the different free‐cooling techniques should be increased by between 100 and 200% to ensure the same living comfort. The results presented in the study confirm that it is necessary to evaluate the consequences of global climate changes from the point of view of energy use in buildings, their construction and the buildings' service installations. Copyright © 2008 John Wiley & Sons, Ltd.     

The California energy approach: From conventional to alternative energy sources

The paper outlines the work of a State Government Agency, the California Energy Commission, which is now completing its major analytical task—forecasting California's future energy demand five, ten and twenty years hence and formulating an optimal state strategy for energy production and conservation.The method used in earlier demand forecasts was simply to extrapolate the trend of past years. These forecasts, prepared mainly by the utilities, lead to alarmingly high figures.By contrast, the approach of the Commission was to study, in depth, the evolution of the demand of each category of end users. Supplemented by a realistic assessment of the impact of various conservation measures and by extensive discussions with different groups of concerned citizens, the Commission's approach produced much lower and quite manageable estimates of future energy demand.In devising an energy supply strategy, the Commission postulated a mix of conventional and alternative energy technologies of proven practicability and diverse lead times. Providing such latitude in the choice of energy options increases the flexibility of the state's strategy to cope with possible unforeseen developments.At this point, the Commission feels that the time is ripe to shift the emphasis of its work from the analysis to the implementation stage.     

A conceptual framework for estimating the climate impacts of land-use change due to energy crop programs

In this paper I discuss general conceptual issues in the estimation of the impacts of CO₂ emissions from soils and biomass, over time, as a result of land-use change (LUC) due to increased demand for energy crops. The effect of LUC on climate depends generally on the magnitude and timing of changes in soil and plant carbon, and in particular on the timing and extent of the reversion of land to original ecosystems at the end of the bioenergy program. Depending on whether one counts the climate impacts of any reversion of land uses, and how one values future climate-change impacts relative to present impacts, one can estimate anywhere from zero to very large climate impacts due to land-use change (LUC). I argue that the best method is to estimate the net present value (NPV) of the impacts of climate change due to LUC. With this approach, one counts the reversion impacts at the end of the program and applies a continuous discounting function to future impacts to express them in present terms. In this case, the impacts of CO₂ emissions from the initial LUC then are at least partially offset by the impacts of CO₂ sequestration from reversion.     

Expected impacts on greenhouse gas and air pollutant emissions due to a possible transition towards a hydrogen economy in German road transport

Transitioning German road transport partially to hydrogen energy is among the possibilities being discussed to help meet national climate targets. This study investigates impacts of a hypothetical, complete transition from conventionally-fueled to hydrogen-powered German transport through representative scenarios. Our results show that German emissions change between ?179 and +95 MtCO₂eq annually, depending on the scenario, with renewable-powered electrolysis leading to the greatest emissions reduction, while electrolysis using the fossil-intense current electricity mix leads to the greatest increase. German energy emissions of regulated pollutants decrease significantly, indicating the potential for simultaneous air quality improvements. Vehicular hydrogen demand is 1000 PJ annually, requiring 446–525 TWh for electrolysis, hydrogen transport and storage, which could be supplied by future German renewable generation, supporting the potential for CO₂-free hydrogen traffic and increased energy security. Thus hydrogen-powered transport could contribute significantly to climate and air quality goals, warranting further research and political discussion about this possibility.     

Genetic algorithm approach to estimate transport energy demand in Turkey

Transport energy modeling is a subject of current interest among transport engineers and scientists concerned with problems of sustainable transport. Transport energy planning is not possible without a reasonable knowledge of past and present energy consumption and likely future demands. In this study, three forms of the energy demand equations are developed in order to improve transport energy demand estimation efficiency for future projections based on genetic algorithm (GA) notion. The Genetic Algorithm Transport Energy Demand Estimation (GATEDE) model is developed using population, gross domestic product and vehicle-km. All equations proposed here are linear and non-linear, of which one is linear, second is exponential and third is quadratic. The quadratic form of the GATEDE model provided better-fit solution to the observed data and can be used with a high correlation coefficient for Turkey's future transport energy projections. It is expected that this study will be helpful in developing highly applicable and productive planning for transport energy policies. The GATEDE gives transport energy demand in comparison with the other transport energy demand projections. The GATEDE model plans the sectoral energy demand of Turkey until 2020.     

Energy efficiency as a resource in state portfolio standards: Lessons for more expansive policies

In this paper, state electricity portfolio standards in the U.S. are analyzed to examine how energy efficiency is being created as a particular kind of resource through this type of climate change governance. Such policies can incentivize energy efficiency by requiring or encouraging electricity providers to meet a certain percentage of their demand through energy efficiency measures. North Carolina’s portfolio standard is used as an in-depth case study to identify factors that are then compared across all 36 states that include energy efficiency as part of a portfolio requirement or goal. The main finding of this study is that state portfolio standards tend to emphasize demand-side energy efficiency, or energy efficiency on the customer’s side of the electricity meter, and only rarely incentivize a full range of both demand-side and supply-side efficiency changes. As a result, the amount of energy efficiency and climate change mitigation benefits that are likely to result from this type of portfolio standard policy tool are limited. From this analysis, lessons are drawn out for crafting stronger portfolio standards that incentivize a wider range of efficiency changes across electricity networks.     

GISELA – GIS-based evaluation of land use and agriculture market analysis under global warming

One of the important future issues is how agriculture production can meet the future demand increase due to the population and the income growth. Global warming would give both positive and negative impacts on them. Agriculture is often expected to supply biofuels to meet the growing transportation energy demand and the warming control policy. GISELA – GIS-based evaluation for land use and agriculture production model – is developed to evaluate the current and the potential cropland for rice, wheat, maize and soy-beans production under climate changes. We also assess the food and the feed demand based on the historical regional statistics for world into 18 regions. Finally, we assess the future food market integrating the above supply and demand conditions developing a dynamic optimization model, GISELA. Current GISELA findings are as follows: (1) potential cropland in south America will be extensively cultivated, (2) market price of wheat and soy will gradually go up while that of maize is almost stable in medium yield case, and (3) in the low-yield case, all crop prices hike rapidly in the mid of this century.     

Climate change mitigation with integration of renewable energy resources in the electricity grid of New South Wales,Australia

The implementation of climate change mitigation strategies may significantly affect the current practices for electricity network operation. Increasing penetration of renewable energy generation technologies into electricity networks is one of the key mitigation strategies to achieve greenhouse gas emission reduction targets. Additional climate change mitigation strategies can also contribute to emission reduction thereby supplementing the renewable energy generation participation, which may be limited due to technical constraints of the network. In this paper, the penetration requirements for different renewable energy generation resources are assessed while concurrently examining other mitigation strategies to reduce overall emissions from electricity networks and meet requisite targets. The impacts of climate change mitigation strategies on the demand and generation mix are considered for facilitating the penetration of renewable generation. New climate change mitigation indices namely change in average demand, change in peak demand, generation flexibility and generation mix have been proposed to measure the level of emission reduction by incorporating different mitigation strategies. The marginal emissions associated with the individual generation technologies in the state of New South Wales (NSW) are modelled and the total emissions associated with the electricity grid of NSW are evaluated.     

Measuring persistent and transient energy efficiency in the US

The promotion of US energy efficiency policy is seen as a very important activity. Generally, the level of energy efficiency of a country or state is approximated by energy intensity, commonly calculated as the ratio of energy use to GDP. However, energy intensity is not an accurate proxy for energy efficiency given that changes in energy intensity are a function of changes in several factors including the structure of the economy, climate, efficiency in the use of resources, behaviour and technical change. The aim of this paper is to measure persistent and transient energy efficiency for the whole economy of 49 states in the US using a stochastic frontier energy demand approach. A total US energy demand frontier function is estimated using panel data for 49 states over the period 1995 to 2009 using two panel data models: the Mundlak version of the random effects model (which estimates the persistent part of the energy efficiency) and the true random effects model (which estimates the transient part of the energy efficiency). The analysis confirms that energy intensity is not a good indicator of energy efficiency, whereas, by controlling for a range of economic and other factors, the measures of energy efficiency obtained via the approach adopted here are. Moreover, the estimates show that although for some states energy intensity might give a reasonable indication of a state’s relative energy efficiency, this is not the case for all states.     

中国太阳能资源评估及其利用效率研究进展与展望

围绕太阳能资源分布特征、资源潜力评估和太阳能利用效率的研究,从中国太阳能资源估算及其分布特征、中国太阳能资源潜力评估、太阳能利用方式及其太阳能利用效率研究、光伏发电效率评估、气候变化因子对光伏发电效率的影响等方面,归纳凝练了太阳能资源评估及其利用效率研究的主要成果。结合相关研究的国际前沿、热点问题和社会经济发展需求,剖析了研究中存在的不足和问题;提出加强气候变化背景下太阳能高辐射区光能资源变化新特征研究、深化太阳能高辐射区太阳能发电效率评估研究、深入开展气候变化因子对光伏发电效率的影响及其机制的研究、细化光能开发潜力评估、进一步完善光伏发电效率预测系统、推动绿色低碳社会经济发展等中国未来太阳能资源评估及利用研究需要重点关注的方向。