Making tomorrow’s buildings more energy efficient

Making tomorrow’s buildings more energy efficient
Published: 04 July 2006

According to the International Energy Agency, the consumption of coal, oil and gas rose by 700% between the early 1960s and the year 2000. Today approximately 40% of the total energy used in OECD countries is used in buildings. The goals of the WBCSD’s project on energy efficiency in buildings are energy self-sufficiency and carbon neutrality at reasonable costs by 2050.

China has decided to make energy efficiency a top priority and as such has included some significant goals in its 11th five-year plan: doubling GDP by 2010 (which would actually suggest a slowing of recent growth rates) and reducing energy intensity in GDP by 20% over the same period. It also plans to build the equivalent of one New York City a year in terms of new buildings.

According to Qiu Baoxing, China’s vice minister of construction, China plans to transform all existing buildings into energy-saving buildings by 2020. He said that from 2006 onward, all new building projects would embrace new technology that could save 65% more energy per square meter than previous constructions. Ministry statistics show that energy consumption per unit for Chinese construction is two to three times that of developed countries.

Currently, energy-saving buildings in China occupy less than one per cent of the country’s total construction by square meter, and only 10% of all buildings meet the minimum standards, according to the China Building Materials Industry Association (CBMIA).

“Although the cost of green buildings, saving 60% of the energy per unit, is only 5-7% higher than the ordinary buildings, it will greatly reduce energy consumption and environment pollution,” Mr. Qui said at a press conference last year.

The potential of energy-efficient buildings is drawing increasing support worldwide. The American Institute of Architects (AIA) predicts that the cost savings and environmental benefits that can be realized throughout the lifetime of a building far outweigh the initial costs of new building concepts.

To further promote the subject in China, the CBMIA and the WBCSD signed an agreement in March to investigate opportunities to improve the sustainability of buildings and their construction materials.

CBMIA president Zhang Renwei welcomed the opportunity to cooperate with the WBCSD on these important activities, particularly in the light of the new five-year plan, which also calls for large reductions in energy use in the cement and building sectors.

WBCSD companies are also taking a concerted look at the challenges and opportunities of energy efficient building. This council-wide project on the subject aims to determine how buildings can be designed and constructed so that they use zero net energy, are carbon neutral, and are built and operated at fair market values. Kicked off in Beijing in March, the project has attracted enormous interest among the 180 multinationals within the organization’s membership.

The effort is led by United Technologies Corp. (UTC) the world’s largest supplier of capital goods including elevators, cooling/heating and onsite power systems to the commercial building industry, and the Lafarge Group, a world leader in construction materials, including cement and roofing.

The group aims to explore means of transforming the way buildings are conceived, constructed, operated and decommissioned. Constructing buildings that use no net energy will require a combination of onsite power generation and ultraefficient building materials and equipment.

The project will draw a roadmap to transform the building industry. It will document existing green building successes and setbacks, identify the full range of present and future opportunities, and present a unified industry strategy for realizing those opportunities by 2050, specifically in China, India, Brazil, the US and EU. The process will be inclusive and involve other initiatives, and hearings and conferences with building contractors and suppliers, sustainability experts, government representatives, regulators, utility officials and others.

The trick is not what is possible, but how to make it affordable, said Christian Kornevall, the project director at the WBCSD, during the project’s launch in Beijing. “We will be exploring a fast lane to see what deliverables could be made commercially viable already by 2010.”

Illustrating some of the efficiencies within reach, George David, CEO of UTC, said: “More than 90% of energy extracted from the ground is wasted before it becomes useful work. A third of this loss comes from waste heat vented to the atmosphere in central generating plants. Although we lose 7% in transmitting electricity, we lose all of the energy in the heat that can’t be transmitted over any significant distance at all. The solution is to generate the power onsite, where the heat can be captured. We build products like this today, with energy conversion efficiencies of over 80%. The heat powers air conditioning via an absorption chiller cycle and comparably can power refrigeration, dehumidification and hot water.”

“Green buildings” have already been erected in various parts of the world, but current cost structures prevent widespread adoption by general contractors. The project will build on these examples, aligning costs and benefits in the building equation and working in close collaboration with architects, builders, suppliers and building owners to promote a more sustainable approach to construction. Existing standards for energy efficiency in buildings will be the starting point for the industry-led alliance.

“Lafarge has been leading efforts in energy efficiency and sustainable construction in the building materials sector for a number of years, not only by reducing greenhouse gas emissions during the production process, but also by developing materials that contribute to making buildings more energy efficient,” said Bertrand Collomb, Chairman of Lafarge.

WBCSD President Björn Stigson noted: “Being smarter and more efficient about how we use energy in buildings will help us conserve energy, reduce greenhouse gas emissions and address climate change. We believe this initiative can provide extremely cost-effective solutions. It will also set the course for self-sufficient and environmentally sound buildings in which future generations will live, work and enjoy their life.”