IPCC Fourth Assessment Defines Role of Buildings in Climate Change Mitigation
June 01, 2007
IPCC has been releasing major sections of "Climate Change 2007" throughout the year. The third section is dedicated to the issue of mitigating greenhouse gas (GHG) emissions. The section's authors, "Working Group III," released a preview this month. Decision makers should carefully consider these findings when evaluating energy-related features or upgrades.
Why IPCC included buildings among the seven sectors evaluated
"Key mitigation technologies and practices currently available include efficient lighting and daylighting, efficient heating and cooling, improved insulation, and solar designs for heating and cooling."
Since the problem of GHGs was discovered, one fact has been clear: Buildings consume energy, and thereby cause GHG emissions. Reducing consumption reduces emissions, but is it a significant amount? IPCC thinks so -- enough for buildings to warrant their own sector among the seven analyzed. (See table.)
Between 1970 and 1990, direct emissions from buildings (commercial and residential) grew by 26 percent, and remained at approximately at 1990 levels thereafter. However, the buildings sector has a high level of electricity use and hence the total of direct and indirect emissions in this sector is 75 percent higher than direct emissions.
Here's a condensed summary of the IPCC "Working Group III" findings, with an emphasis on commercial and industrial topics within it.
Greenhouse gas emissions can be mitigated for a price
Global greenhouse gas emissions have grown since pre-industrial times, with an increase of 70 percent between 1970 and 2004. With current climate change mitigation policies and related sustainable development practices, emissions will continue to grow over the next few decades.
Change will come at a price. In 2030 the global average costs for stabilizing emissions will cause at most a three percent decrease of global GDP. In IPCC's more optimistic scenarios, a small increase in GDP is possible.
There is substantial economic potential for the mitigation of global GHG emissions over the coming decades, which could offset the projected growth of global emissions or reduce emissions below current levels. Near-term health benefits from reduced air pollution may offset a portion of the mitigation costs.
How to mitigate GHG emissions economically between now and 2030
Changes in lifestyle and behavior patterns can contribute to climate change mitigation. Education in energy efficiency, building occupant behavior to reduce energy consumption in buildings, advances in technology, and corporate management practices can also have a positive role.
Energy infrastructure investment decisions are expected to total over US$20 trillion between now and 2030. New investments in developing countries, upgrades of energy infrastructure in industrialized countries, and policies that promote energy security can help to achieve GHG emission reductions.
Where reductions will come from
Energy efficiency improvements are a more cost-effective investment than increasing energy supply, and improve energy security.
Renewable energy can have a 30 percent to 35 percent share of the total electricity supply in 2030. Use of renewables improve energy security and employment, as well as air quality.
Nuclear energy's share will grow marginally, constrained by concerns about waste and other issues.
Additional benefits include air pollution abatement, balance of trade improvement, modern energy services for rural areas, and employment.
Buildings and industry have a major role in mitigation
Through energy efficiency, about 30 percent of the projected GHG emissions in the building sector can be avoided with a net economic gain. Energy efficient buildings limit the growth of CO2 emissions, while they also improve indoor and outdoor air quality, improve social welfare and enhance energy security.
There are barriers to tapping this potential, especially in developing countries. The barriers include the availability of technology, financing, poverty, higher costs of reliable information, limitations inherent in building designs and an appropriate portfolio of policies and programs.
Key mitigation technologies and practices are currently commercially available. They include efficient lighting and daylighting, efficient heating and cooling, improved insulation, passive and active solar designs for heating and cooling, alternative refrigeration fluids, and the recycling of fluorinated gases.
More will be commercialized before 2030. They include the integrated design of commercial buildings, incorporating technologies such as intelligent meters and building-integrated photovoltaics (BIPV).
Industry faces greater challenges
The economic potential in the industrial sector is predominantly in energy intensive industries. Neither industrialized nor developing nations are making full use of available mitigation options. Upgrading older, inefficient facilities can deliver significant reductions, but capital stock turnover is slow.
Policies to mitigate climate change
A wide variety of national policies and instruments are available to governments to create the incentives for mitigation action. An effective carbon-price signal could realize significant mitigation potential in all sectors, especially power generation. Policies that put a price on carbon could create incentives for investment.
Measures that are environmentally effective Key constraints or opportunities BUILDINGS
Building codes and certification
Attractive for new buildings. Enforcement can be difficult
Demand-side management programs
Need for regulations so that utilities may profit
Public sector leadership programs, including procurement
Government purchasing can expand demand for energy efficient products
Incentives for energy service companies (ESCOs)
Success factor: Access to third-party financing
Provision of benchmark information, performance standards, subsidies, tax credits
May be appropriate to stimulate technology uptake. Stability of national policy important in view of international competitiveness
Predictable allocation mechanisms and stable price signals important for investments
Success factors include: clear targets, a baseline scenario, third party involvement in design and review and formal provisions of monitoring, close cooperation between government and industry.
Fourth Assessment is most thorough yet, but will be a target for critics
IPCC is criticized for being too conservative in its evaluations, and for not sufficiently incorporating the views of climate-change skeptics. The reporting process is long and consensus is tedious work; late-breaking developments excluded from the reports can make them seem out of date by the time they are published.
IPCC issued its First Assessment report in 1990. The third and most recent published report was issued in 2001. The full Fourth Assessment, expected to be published in October 2007, is considered to have the strongest agreement among Panel participants.