A COMPARISON OF BUILDING ENERGY EFFICIENCY STANDARDS BETWEEN UK AND CHINA

A Comparison of Building Energy Efficiency Standards between UK and China

Table of Contents

4.2. Comparison of total costs across the scenarios7

4.2.1. Exclusion of carbon emission cost7

4.2.2. Inclusion of carbon emission cost10

5. CONCLUDING REMARKS13

Table 4.

Gas-fired district boiler (heat only).

2006

2015

2025

GWh

1000 t C

GWh

1000 t C

GWh

1000 t C

TJ-97

3225

172

3573

191

4042

216

TJ-WB97

2896

155

3211

171

3644

195

TJ 2004

2568

137

2850

152

3247

173

TJ-WB04

2479

132

2753

147

3140

168

TJ-CAN

2431

130

2700

144

3082

165

TJ-RT2005

2273

121

2526

135

2891

154

TJ-SWE

2061

110

2279

122

2605

139

Table 5.

Gas-fired district small CHP.

2006

2015

2025

GWh

1000 t C

GWh

1000 t C

GWh

1000 t C

TJ-97

3741

100

4147

112

4688

128

TJ-WB97

3356

95

3724

105

4223

120

TJ 2004

2989

89

3321

98

3779

111

TJ-WB04

2868

88

3187

96

3633

109

TJ-CAN

2812

87

3127

95

3566

108

TJ-RT2005

2602

84

2895

92

3312

103

TJ-SWE

2341

80

2586

87

2948

96

Table 6.

Municipal large CHP.

2006

2015

2025

GWh

1000 t C

GWh

1000 t C

GWh

1000 t C

TJ-97

5266

163

5803

197

6500

242

TJ-WB97

4706

146

5188

177

5823

217

TJ 2004

4171

129

4600

157

5177

193

TJ-WB04

3994

124

4406

150

4964

185

TJ-CAN

3914

121

4318

147

4867

181

TJ-RT2005

3607

112

3981

135

4496

168

TJ-SWE

3228

100

3531

120

3966

148

Table 7.

Individual gas boiler.

2006

2015

2025

GWh

1000 t C

GWh

1000 t C

GWh

1000 t C

TJ-97

2227

119

2453

131

2755

147

TJ-WB97

2011

107

2216

118

2493

133

TJ 2004

1804

96

1989

106

2244

120

TJ-WB04

1736

93

1914

102

2161

115

TJ-CAN

1705

91

1880

100

2124

113

TJ-RT2005

1586

85

1750

93

1981

106

TJ-SWE

1440

77

1575

84

1776

95

Note: Primary energy demand consumed for electricity generation in CHP is not subtracted in Table 2, Table 3, Table 4, Table 5, Table 6 and Table 7, this explain why CHPs have higher primary energy supply.

However, prudence is necessary when interpreting the difference between the energy supply options. First, the scenario of individual gas boiler option appears to be the best scenario in terms of primary energy savings, but it disguises the fact that electricity is also generated in all the scenarios with cogeneration option. Indeed, the primary demand in heat-only scenarios must be much higher if upstream energy consumption for electricity generation is taken into account. Second, gas-fuelled energy supply system appears to be preferred to coal-fired district heating if the primary objective is the CO2 emission mitigation. However, fuel-switching policy should be assessed much more deeply than just comparing the carbon emission outcome, the economic dimension should not be ignored. More convincing decision on investment strategies can be made through the insights in the analysis of costs in Section 4.2.

4.2. Comparison of total costs across the scenarios

All costs incurred in buildings and energy supply over the modelling are discounted to the base year (2006) and are accounted for as yuan/m2 floor space to harmonise the criteria for comparison, since the unitary incremental cost related to BEE measures is expressed systematically in buildings construction programme. Cost scenarios with and without carbon price are both investigated.

4.2.1. Exclusion of carbon emission cost

Fig. 8 illustrates the total costs in all BEE and energy supply scenarios. Some important lessons can be drawn immediately by comparing the different scenarios:

1. All scenarios show that the current national BEE standard (TJ-97 equivalent efficiency requirements) is the most costly option, no matter what supply option will be selected.

2. Despite considerable progress compared with national objective, the BEE standard implemented in Tianjin (TJ 2004) is not stringent enough to allow achieving an optimal level since the present value of total costs incurred during a 20-year period can be reduced further by tightening the building code, even with a relatively high discount rate (8%).

3. Without any carbon price imposed, the optimal choice turns out to be the equivalent of current French RT-2005 building efficiency standard coupled with district coal-fired CHP, which allows for the lowest present value of the overall discounted costs (490 yuan/m2 floor space).

4. Lastly but most strikingly, we observe that adopting the best available technology (BAT), or the equivalent energy performance prescribed in the Swedish BEE standards is less costly than the current BEE regulations enforced in China and Tianjin regardless of energy supply system.

q

Fig. 8. Comparison of discounted total cost in different energy supply ...