DH source combinations
Average investment
Individual
Basic
Classic
Heat source technology
MILLION £/MW-heat
MW
MW
MW
Individual HP air-to water
86
HP air-water
0.731
30.0
20
CHP Gas engine back pressure
0.954
Electric boiler
0.060
Natural gas boiler
0.051
30
30
High-gradewaste heat source
0
Storage (1) Investment per MWh capacity
0.0026
50
Total production capacity MW-heat
86
60
Investment production million £
105
23
16
Investments household units million £
13
13
Investment production million £
105
37
29
Saved investments before network
35%
28%
Investment DH network £/MWh-heat
13.9
13.9
Investments £/MWh-heat
42.1
28.6
20.4
Reduced Investment % of basic
29%
Table 3: Comparison of individual heat delivery and basic and classic heat source design
demand if the heat pump is not running.
demand is covered by the large air-to-water heat pump and a similar large boiler for reserve capacity. In the classic design, capacity demand is covered by a 70% air-to-water heat pump(20 MW) and a large gas boiler, both delivering peak load demand and reserve load demand (30 MW). Investments in district heating units and district heating networks are included in calculations, and the total investments are transformed into investments per delivered MWh-heat in a lifetime. The data used from the Danish Technology catalog regarding network investments provide a price per MWh of delivered heat per year. The capacity demand for district heating is calculated to be 28.6 MW, and the chosen capacity is 30 MW, which is around 5% oversized compared to actual demand. The boiler size is kept in classic design, allowing the boiler to cover all heat
The technical lifetime of district heating production technologies and heat networks is substantially longer than that of individual technologies, and results show that total investments are significantly lower than individual solutions when compared per MWh delivered, including DH network investments. The change in design from 100% base load coverage to 70% coverage of baseload capacity reduces the total investments to 7.3 million £. The heat production costs, though, will be slightly higher in the classic design (2.32 £/MWh-heat) compared to the basic design but not on a level with the saved investment costs (8.19 £/MWh-heat).
DH source combinations
WP + HP + storage
WP + HP + storage
Average investment Individual
Basic Classic HP + CHP HP + CHP + storage
Heat source technology
Million £/MW-heat
MW MW MW MW MW MW MW
Individual HP air-to water
86
HP air-water
0.731
30
20
10
10
10
5
CHP Gas engine back pressure
0.9537
10
10
10
5
Electric boiler
0.0595
10
10
10
10
Natural gas boiler
0.051
30
30
10
10
10
10
High-gradewaste heat source
0
10
15
Storage (1) Investment per MWh capacity
0.002
200
200
200
Total production capacity MW-heat
86
60
50
40
40
50
45
Investment production million £
105
23
16
18
18
18
10
Investments household units million £
13
13
13
13
13
13
Investment production million £
105
37
29
31
32
32
23
Saved investments before network
35% 28% 30% 30% 30% 22%
Investment DH network £/MWh-heat
13.9 13.9 13.9
13.9
13.9
13.9
Investments £/MWh-heat
42.1
28.6 20.4 21.1
21.3
21.3
17.9
Reduced Investment % of basic
29% 26% 25% 25% 37%
Table 4: Different combinations of heat source design and total investments per MWh-heat
22 HOTCOOL no.6 2024
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