Implications of climate changes to building energy and design
Introduction
Climate change is widely acknowledged a primary environmental problem facing the planet. The Intergovernmental Panel on Climate Change (IPCC) estimated that between 1970 and 2004, global greenhouse gas emissions rose 70% (IPCC, 2007). Many of the effects of the building sector on climate change are well explored. The building sector contributes up to 30% of global annual greenhouse gas emissions and consumes up to 40% of all energy (IPCC, 2007). Furthermore, between 1971 and 2004, carbon emission is estimated to have grown at a rate of 2.5% per year for commercial buildings and at 1.7% per year for residential buildings (Levine, Urge-Vorsatz, Blok, Geng, Harvey, & Lang 2007). However, many of the potential effects of climate change on the building sector are not well studied. Changes in climate will have significant impacts on built environments and thus their designs and operations, and hence it will be crucial to understand these effects.
A few methods exist to analyze implications of climate change to building energy use. In early studies, a simple degree day based method was used (Amato, Ruth, Kirshen, & Jorwitz, 2005; Olonscheck, Holsten, & Kropp, 2011; Rosenthal, Gruenspecht, & Moran, 1995). The main principle of this method is that the building energy use is proportional to the heating and cooling degree hours for the location of the building. This method can provide an estimate of the impact of climate change (if future outdoor temperature is used) on buildings. However, this approach only accounts for sensible load because merely the dry bulb temperature (dbt) is taken into consideration. Solar radiation, humidity and other building characteristics are not considered.
Detailed hour by hour building energy simulation tools were recently used to study the impacts of climate change on building energy use (Chan, 2011; Cooper, 2010; Wang & Chen, 2014; Wang, Chen, & Ren, 2010). Most of these studies used several climate models to predict the influences of climate changes on a few typical building models. For instance, Wang, Liu, and Brown, (2017) used the HadCM3 and CESM1 climate projection models to predict the impacts of climate change on energy consumption for a medium-size office building and tested a set of HVAC operation related mitigation measures to offset the influences. Cellura, Guarino, and Sonia Longo (2018) used a Global Circulation Model (GCM) data to model the energy implications to an office building in Southern Europe that shows the increase in air temperature in South EU up to 9 °C and the cooling energy cooling increase up to 120% in 2090. Spandagos and Ng (2017) predicted the climate change impacts on building cooling and heating energy in large Asian cities and concluded that switching to more efficient air-conditioning devices can offset much of the increases, while Hwang, Shih, Lin, and Huang (2018) concluded that thermal insulation is gaining more concern while climate change proceeds. Pérez-Andreu, Aparicio-Fernández, Martínez-Ibernón, and Vivancos (2018) predicted the impacts of climate change on heating and cooling energy demand in a residential building in a Mediterranean climate with two GCMs for 2050 and 2100. The study indicated that heating energy demand decreases significantly, and cooling energy demand increases. They also suggested thermal insulation and infiltration have the greatest effect on total energy demand. Jiang and O’Meara (2018) also explored a series of thermal features of commercial building systems to mitigate energy consumption in Florida due to global climate change. Aijazi and Brager (2018) presented an overview and a case study to demonstrate how climate change impacts on building can be simulated and will vary by building type and location. It is generally agreed that the climate change impact on energy demand is sensitive to building type and location. Huang and Gurney (2016a) predicted that the warehouse showed an increase of >100% energy consumption at some summer hours while the secondary school building showed an increase of >39% energy consumption in August. At climate zone scale, changes in annual energy consumption can range from −17% to +21%. Schuetter, Debaillie, and Ahl (2014) used energy modeling to investigate effects of future climate change on energy consumption, peak demand and energy costs at NASA’s John C. Stennis Space Center in southern Mississippi. This was a rare example of predicting future climate change influence on a real building stock modeled using representative buildings. This study used only two future climate change sets provided by the North American Regional Climate Assessment Program (NARCCAP) – a high and low impact scenario. They found that the total annual projected energy was expected to increase 8.6% and 17.7% for the low and high scenarios.
More comprehensive studies were also found in literature. Shen (2017) integrated one GCM data to the typical meteorological year weather file to predict local hourly weather data in US using a morphing methodology. Case studies in four representative cities in the U.S. showed that the change of annual energy use is predicted to range from −1.64% to 14.07% for residential building and from −3.27% to −0.12% for office building under A2 scenario (a carbon emission scenarios defined by IPCC) in different regions in 2040–2069. The research suggested that the climate change will narrow the gap of energy use for residential buildings located in cold and hot climate regions in the U.S. and generally reduce office building energy use in the future. It was also found that the energy use of lightings and fans will slightly decrease in the future, but the growing peak electricity load during cooling seasons is going to exert greater pressure for the future grid. Rey-Hernández, Yousif, Gatt, Velasco-Gómez, José-Alonso, and Rey-Martínez (2018) modeled the long-term effect of climate change on a zero energy and carbon dioxide building through energy efficiency and renewable. Results showed that the cooling demand would significantly increase for the years 2050 and 2080, while space heating would drop. The previously excess generated electricity of the building by photovoltaics would then be totally consumed within the building due to increased demand, implying longer operation hours and thus more maintenance and replacement costs. Cao, Li, Wang, Xiong, and Meng (2017) investigated the effects of climate change on building energy-saving design in the different climate zones of China and found that the increasing rate of design temperatures for both heating and air-conditioning in winter were in the range of 0.2 °C – 0.7 °C/decade, and the rate of design temperature for air-conditioning in summer was in the range of 0.1 °C – 0.4 °C/decade. Angeles, González, and Ramírez (2018) assessed the impacts of climate change on building energy demands in the intra-Americas region using the Intergovernmental Panel on Climate Change (IPCC) Representative Concentration Pathways (RCP) 2.6 and 4.5 scenarios and forecasted an increase of 9.6 and 23 kW h/month, respectively by the end of the twenty-first century, which may increase average building cooling loads in the region by 7.57 GW (RCP2.6) and 8.15 GW (RCP4.5), respectively.
One a large scale, Gi, Sano, Hayashi, Tomoda, and Akimoto (2018) analyzed the global residential heating and cooling demands for different climate change scenarios up to 2050. They concluded that the space heating and cooling demand in 2050 in the world as a whole become 2.1–2.3 and 3.8–4.5 times higher than those for 2010, upon different global warming scenarios. Clarke, Eom, Marten, Horowitz, Kyle, and Link (2018) studied the effects of long-term climate change on global building energy expenditures and concluded that net expenditures decrease in some regions where heating demands currently dominate while net expenditures increase the most in areas with greater demand for space cooling. Reyna and Chester (2017) indicated that without policy intervention, residential electricity demand could increase by as much as 41–87% between 2020 and 2060. However, aggressive policies aimed at upgrading heating/cooling systems and appliances could result in electricity use increases as low as 28%, potentially avoiding the installation of new generation capacity. Huang and Gurney (2016b) suggested that the changes at the state/month scale that are much larger with summer electricity demand increases exceeding 50% and spring non-electric energy declines of 48% by the end of the century, while the US national/annual total source energy consumption differences between the 2080–2099 time period and the present are less than 2%. Huang and Gurney (2017) further estimated the financial implications of climate change on U.S. building energy demand. They estimated that building energy costs decrease by ∼7 billion $/year in the residential sector, while increase by ∼2.2 billion $/year in the commercial sector. For cold-weather states, there are residential energy savings of up to 340 $/year, while warmer states see increased residential energy costs of up to 231 $/year per household. The increased summertime cooling demand poses important questions for the electricity supply system. They also indicated that to maintain a reliable electricity supply requires an additional 80.6 GW (GW) of capacity.
The literature review reveals a wide range of predicted energy demand changes for buildings under projected future weathers due to different building types, locations, building models, and climate models used. Although general trends were observed as commonly sensed, some contradictive conclusions were presented. It indicates a need for a more comprehensive study that utilizes and analyzes a larger number of climate models and scenarios, as well as developing representative climate models that can cover a full range of possible future conditions. Most studies predate the IPCC Fifth Assessment Report (AR5) so the models and scenarios that were used have since been upgraded. The AR5 covers a larger range of scenarios than the Special Report on Emissions Scenarios (SRES) used in previous assessments (IPCC, 2014). When comparing the AR5 scenarios to the previous SRES scenarios, 3 of the 4 have an equivalent scenario. However, the stringent mitigation scenario has no equivalent, therefore there will be a difference in magnitude of the SRES and AR5 climate projections due to a wider range of emissions scenarios (IPCC, 2014). Using a large number of AR5 projections will allow a better estimate on the range of how climate change may affect a particular building or building stock.
Section snippets
Overview
Climate models have been developed and used to project climate changes, upon a standard set of greenhouse gas scenarios called Representative Concentration Pathways (RCPs) used in the IPCC Fifth Assessment Report (AR5). RCPs describe four different 21st century pathways of greenhouse gas (GHG) emissions and atmospheric concentrations, air pollution and land use. They include a stringent mitigation scenario (RCP2.6), two intermediate scenarios (RCP4.5 and RCP6.0), and one scenario with very high
Analysis of projected climate data
The 56 model scenarios were first grouped into their respective RCP groups. For each group, an average, standard deviation and range of cooling degree day (CDD) was calculated. The cooling degree days (CDD) and heating degree days (HDD) are calculated hourly over a year using Eqs. (1) and (2):where Tb is the balance point temperature at which the building does not require heating or cooling (common values of 10 °C and 18 °C were used here for calculating
Development of reference climate models
For application convenience, four reference climate models were identified to fully encompass the range of all 56 model scenarios. These four identified reference models act like the 12.5%, 87.5% and median models, with the high one covering the top 12.5% of the range, the low one covering the bottom 12.5%, while the other two covering the median 75% of the predicted range (as illustrated in Fig. 2). To ensure that the reference models hold true for all cities and time periods, 21 hourly
Campus model
It is more important to understand the impacts of climate change on building energy use at a large scale (e.g., district, city, or even region) than individual buildings. Predicting building energy use at a city level is a complicated process, and few approaches are available. Lim (2016) proposed a probabilistic based stochastic deterministic coupled method to estimate the distribution of building energy consumption at a large scale. The proposed methodology was applied here to a campus scale
Implications of climate change to building energy policies and standards
Prediction of how climate change will affect building stocks can provide quantitative insight to how a city and local authority will need to adapt. Building codes and standards should take the prediction of climate change into consideration. ASHRAE bases building envelope and system standards on climate zone so as to optimize building performance. This study demonstrates that in the near future climate zones may change. Buildings being built for one climate zone (and code) may under preform in
Discussions and conclusions
When applying climate models to project future climate change scenarios, a limited number of models were often used. Analysis of 56 newest model scenarios approved from the IPCC revealed that the range of model projections varies significantly. Within each RCP scenario, results from a simple degree day analysis indicate that this range can have a large impact on the predicted energy consumption of building stock. Four representative climate models were identified for application convenience
Acknowledgement
The first author gratefully acknowledges the funding from USAID through the SHERA program - Centre for Development of Sustainable Region (CDSR).
References (31)
- et al.
Climate change and the building sector: Modelling and energy implications to an office building in southern Europe
Energy for Sustainable Development
(2018) - et al.
Effects of climate change on outdoor meteorological parameters for building energy-saving design in the different climate zones of China
Energy and Buildings
(2017) Developing future hourly weather files for studying the impact of climate change on building energy performance in Hong Kong
Energy and Buildings
(2011)- et al.
Effects of long-term climate change on global building energy expenditures
Energy Economics
(2018) - et al.
The variation of climate change impact on building energy consumption to building type and spatiotemporal scale
Energy
(2016) - et al.
Impact of climate change on U.S. building energy demand: Financial implications for consumers and energy suppliers
Energy and Buildings
(2017) - et al.
Simplification and adjustment of the energy consumption indices of office building envelopes in response to climate change
Applied Energy
(2018) - et al.
Accommodating thermal features of commercial building systems to mitigate energy consumption in Florida due to global climate change
Energy and Buildings
(2018) - et al.
Heating and cooling energy demand and related emissions of the German residential building stock under climate change
Energy Policy
(2011) - et al.
Impact of climate change on heating and cooling energy demand in a residential building in a Mediterranean climate
Energy
(2018)
Modelling the long-term effect of climate change on a zero energy and carbon dioxide building through energy efficiency and renewables
Energy and Buildings
Impacts of climate change on U.S. Building energy use by using downscaled hourly future weather data
Energy and Buildings
Equivalent full-load hours for assessing climate change impact on building cooling and heating energy consumption in large Asian cities
Applied Energy
Impact of climate change heating and cooling energy use in buildings in the United States
Energy and Buildings
Prediction of the impacts of climate change on energy consumption for a medium-size office building with two climate models
Energy and Buildings
Cited by (110)
Resilience of the higher education sector to future climates: A systematic review of predicted building energy performance and modelling approaches
2024, Renewable and Sustainable Energy ReviewsBalancing thermal comfort and energy efficiency in high-rise public housing in Hong Kong: Insights and recommendations
2024, Journal of Cleaner ProductionEnhancing school buildings energy efficiency under climate change: A comprehensive analysis of energy, cost, and comfort factors
2023, Journal of Building EngineeringImpacts of climate change and building energy efficiency improvement on city-scale building energy consumption
2023, Journal of Building Engineering