Climate protection through energy efficiency in buildings (baseline study)
Title: Climate protection through energy efficiency in buildings – baseline study to determine the heating energy demand of the housing stock in northern China as a basis for a carbon emissions trading platform
Commissioned by: German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB)
Lead executing agency: Ministry of Housing and Urban-Rural Development (MoHURD)
Overall term: 2010 to 2013
Due to their low energy efficiency, older residential buildings in northern China are a major source of greenhouse gas emissions (GHG emissions). To date, the mechanisms designed to promote energy-efficient retrofitting of such buildings have proved insufficient. A trading platform for carbon emissions in the buildings sector could provide financial incentives for energy-efficient retrofitting and therefore promote the reduction of GHG. However, as far as introducing a carbon emissions trading platform is concerned, there are currently no data to determine the heating energy consumption of residential buildings prior to retrofitting. The project is carrying out energy surveys to compile this data in a baseline study.
A basis for using new financial incentives to carry out large-scale energy-efficient retrofitting of residential buildings is in place. The information required to introduce a trading platform for carbon emissions in the buildings sector, which in turn can help reduce greenhouse gas emissions in future, is available.
In order to carry out the baseline study, a complete inventory of existing residential buildings in need of renovation is being compiled in three selected cities in two different climate zones in northern China. The buildings are then classified into building types and their specific heating energy demand prior to renovation is calculated based on physical parameters of building elements. Using existing meteorological data, the heating energy demand is extrapolated for buildings of the same type for the most important towns and cities in northern China. In order to plan energy-efficient retrofitting, concepts for energy-efficient renovation are drawn up and heating meters are installed. A methodology for a carbon emissions trading platform based on the rules of the Clean Development Mechanism (CDM) is being developed as part of the project. Using this basis and a scenario analysis, the project partners calculate the potential for greenhouse gas reductions as well as the market chances of the methodology. The possibility of extending the methodology to include heating supply companies and distribution networks also exists.
Results achieved so far
By late 2011, inventories of residential buildings in need of renovation had been compiled in cooperation with three chosen cities in northern China, namely Harbin, Shijiazhuang und Yuzhong. A total of 22,540 buildings were surveyed and classified into 29 different types, of which 11 represent more than 90 per cent of the buildings. Chinese and German experts developed a methodology for calculating the heating energy requirement of non-renovated buildings based on a selection of 138 representative buildings. At the same time, so-called k-values measuring the heat loss through all typical elements used in the building shell were calculated. These calculations can in future help local experts to determine heating energy baselines for other building types. The heating energy demand for the same building types in 210 northern Chinese cities can be calculated by applying meteorological data.
Renovation concepts were compiled for all three cities and these are now available to other cities to assist them in their planning. The retrofitting measures always include the installation of heat meters so that the actual consumption in terms of heating energy can be measured once retrofitting is complete. The difference to the heating energy baseline gives the energy-saving which can then be used to calculate the reduction in GHG emissions.
In October 2012, the results were presented to key actors in the Chinese emission trading system (ETS) sector, including the National Development and Reform Commission (NDRC), the Ministry of Housing and Urban-Rural Development (MoHURD) as well as the carbon emissions trading exchanges in Tianjin and Beijing.
The methodology for certificate trading developed in line with the Clean Development Mechanism (CDM) is currently still being refined. Based on measurements carried out following completed renovations, a saving in heating energy of 25 to 30 per cent can be expected. However, depending on the quality of the materials used and the workmanship, this figure may either increase or decrease.
A model for analysing various scenarios for the participation of the residential building sector in carbon emissions trading is in the test phase. Using this model, it will be possible for the first time to see just how certificate trading contributes to energy savings.
he status of heating suppliers and supply networks in China was examined, with the heating reform also being taken into account. Recommendations for carrying out cost-efficient retrofitting in China were drawn from comparisons made with the situation in Germany at the time of reunification. Renovation of entire district heating networks, as well as individual buildings, has been shown to generate the greatest energy savings and the most emission reduction certificates. In order to disseminate this methodology more broadly, the project partners have prepared some initial training materials.