Sustainable Buildings – Facts and Forecasts
Groundswell of Support for More Efficient Buildings
Almost 40 % of the world’s energy is used by buildings. According to the German Energy Agency (DENA), potential savings of 30 % are possible for heat and 15 % for electric power. A study by the German Federal Environment Agency has even calculated that by thoroughly renovating and insulating walls and cellar ceilings in old buildings, and installing double glazed windows, savings of 56 % could be made in terms of heating energy (see Pictures of the Future, Spring 2007, Energy Efficiency).
The global market for heating, ventilation, and air conditioning products is estimated at around €80 billion, according to the German Federal Ministry for the Environment, Nature Conservation and Reactor Safety and the German Institute for Economic Research (DIW); it is also growing at 5 % per year. Future improvements here will come from optimizing existing technologies, such as new types of coolants, and better control and process technology, using sensors and other technologies. Demand for efficient building systems is growing, primarily as a result of stricter legal requirements and energy efficiency campaigns. Of China’s 40 bill. m² of residential and usable floor space, some 16 bill. m² is accounted for by residential buildings within cities. By 2010, the government plans to invest around $400 billion in energy efficiency improvements for buildings. Improvements will be documented in an effort to ensure that only energy-efficient construction plans are approved. This is an important step, since China’s expenditures for new construction are expected to increase by 9.2 % a year until 2010 according to the latest forecast by Freedonia. "Thanks to the introduction of energy use standards for new buildings, we have already saved 5 mill. t of coal between January and October 2007 alone," says Xie-Zhen Hua, Deputy Director of the National Development and Reform Commission.
In the U.S., energy efficiency is growing in importance, particularly in public buildings, even though a study by McGraw Hill Construction in 2007 revealed that the proportion of "green buildings" in the U.S. is still only 0.3 % of residential real estate. The annual increases of 20 to 30 % are, however, significant. By the end of 2007, 4,100 buildings and factories had acquired the "Energy Star" label for energy efficiency, 1,400 of them in 2007 alone. In California, the Building Regulations Committee passed the "California Green Building Standards Code" at the end of July 2008. It contains guidelines aimed at pushing building energy consumption 15 % below the values that are being achieved by current binding energy efficiency standards. The directive is set to become mandatory for residential buildings in 2010.
Europe has various initiatives, such as the "20-20-20 by 2020" motto. This means that by 2020, greenhouse gas emissions are to be reduced by 20 % compared to 1990, the proportion of renewable energies increased to 20 % and energy efficiency increased by 20 %. Another European initiative is the voluntary GreenBuilding program, which has been in place since 2005. Its aim is to improve the energy efficiency of non-residential buildings, such as offices, schools or industrial premises, by helping property owners modernize their buildings (see Interview Bertoldi).
In the context of energy-saving contracting, such investments can pay for themselves out of contractually-agreed savings within a defined period. According to the Berlin Energy Agency, energy costs and carbon dioxide emissions can be cut by an average of up to 30 % in this way.
"Across Germany, efficiency contracting will cut energy costs by some €800 million and carbon dioxide emissions by 4.5 mill. t each year," says Michael Geißler, Executive Manager of the Berlin Energy Agency. By 2010, the agency anticipates the market volume for contracting to reach €4 billion a year. Contracting providers such as Siemens can exploit significant growth potential here, since only around 10 % of the market is being tapped.
Sylvia Trage