3.3.6 Technological and Economic Potential
An estimate of the technological and economic potential of energy efficiency
measures was recently prepared for the IPCC (Acosta Moreno et al., 1996).11
This analysis provides an estimate of energy efficiency potential for buildings
on a global basis. Using the B2 Message marker scenario (Nakicenovic et al.,
2000) as the base case,12
the analysis indicates an overall technical and economic potential for reducing
energy-related CO2 emissions in the buildings sector of 715MtC/yr
in 2010 for a base case with carbon emissions of 2,600MtC/yr (27%), of 950MtC/yr
in 2020 for a base case with carbon emissions of 3,000MtC/yr (31%), and of 2,025MtC/yr
in 2050 for a base case with carbon emissions of 3,900MtC/yr (52%) (see Table
3.5).13
It is important to note that the availability of technologies to achieve such
savings cost-effectively depends critically on significant R&D efforts.
Table 3.5: Technical and economic potential
for reducing energy-related carbon dioxide emissions from the buildings
sector
(Acosta Moreno et al., 1996). |
 |
| |
Projected emissions reductions
(MtC)
|
|
Share of projected total emissions
|
|
| |
2010
|
2020
|
2050
|
|
2010
|
2020
|
2050
|
|
| Developed Countries + EIT Region |
|
|
|
|
|
|
|
| Residential |
325
|
420
|
660
|
|
30%
|
35%
|
54%
|
| Commercial |
185
|
245
|
450
|
|
32%
|
38%
|
68%
|
| Total |
510
|
665
|
1110
|
|
31%
|
36%
|
59%
|
| Developing Countries |
|
|
|
|
|
|
|
| Residential |
125
|
170
|
515
|
|
20%
|
21%
|
39%
|
| Commercial |
80
|
115
|
400
|
|
24%
|
26%
|
57%
|
| Total |
205
|
285
|
915
|
|
21%
|
23%
|
45%
|
| World |
715
|
950
|
2025
|
|
27%
|
31%
|
52%
|
| |
| |
Estimates of the ranges of costs of carbon reductions are based on a synthesis
of recent studies of costs (Brown et al., 1998); these estimates are similar
to those provided in an International Energy Agency Workshop on Technologies
to Reduce Greenhouse Gas Emissions (IEA, 1999a). The qualitative rankings for
the reductions in carbon emissions follow the results of the IPCC Technical
Paper (Acosta Moreno et al., 1996). In general, it is assumed that costs are
initially somewhat higher in developing countries because of the reduced availability
of advanced technology and the lack of a sufficient delivery infrastructure.
However, depending upon conditions in the country or region, these high costs
could be offset by the fact that there are many more low-cost opportunities
to improve energy efficiency in most developing countries.
These studies show that with aggressive implementation of energy-efficient
technologies and measures, CO2 emissions from residential buildings
in 2010 can be reduced by 325MtC in developed countries and the EIT region at
costs ranging from –US$250 to –US$150/tC saved and by 125MtC in developing
countries at costs of –US$200 to US$50/tC saved. Similarly, CO2
emissions from commercial buildings in 2010 can be reduced by 185MtC in developed
countries and the EIT region at costs ranging from –US$400 to –US$250/tC
saved and by 80MtC in developing countries at costs ranging from -US$400 to
US$0/tC saved.
3.3.7 Conclusions
Energy demand in buildings worldwide grew almost 3% per year from 1971 to 1990,
dropping slightly after that as a consequence of the significant decrease in
energy use in the EIT region. Growth in buildings energy use in all other regions
of the world continued at an average rate of 2.5% per year since 1990. This
growth has been driven by a wide variety of social, economic, and demographic
factors. Although there is no assurance that these factors will continue as
they have in the past, there is also no apparent means to modify most of the
fundamental drivers of energy demand in residential and commercial buildings.
However, there is considerable promise for improving the energy efficiency of
appliances and equipment used in buildings, improving building thermal integrity,
reducing the carbon intensity of fuels used in buildings, reducing the emissions
of HFCs, and limiting the use of HFCs to those areas where appropriate. There
are many cost-effective technologies and measures that have the potential to
significantly reduce the growth in GHG emissions from buildings in both developing
and developed countries by improving the energy performance of whole buildings,
as well as reducing GHG emissions from appliances and equipment within the buildings.
