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Energy Atlas Bavaria
Please rate the waste heat calculator
Bavarian State Office for the Environment
Waste heat calculator
Calculation of waste heat potential - Process exhaust air
Your data on the waste heat source
Exhaust air volume flow (m³ / h):
The air volume flow can be read on the fan nameplate or the data sheets.
For systems requiring approval, it is documented in the approval systems.
Current exhaust gas temperature (° C):
The temperature can be measured with the thermometer or taken from the system documentation.
A system thermometer is also often available.
Operating hours per day:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Operating days per week:
1
2
3
4
5
6
7
Operating weeks per year:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Share of annual operating time in the partial load range (%):
Partial load operation of a system reduces the amount of waste heat. Estimate what percentage of your system is operating at partial load instead of nominal load.
For power generation, the waste heat source must be operated at rated load throughout the year.
Further information
0
10
20
30
40
50
60
70
80
90
100
Average system capacity in part-load operation, relative to the rated load (%):
The system output can be more or less reduced in partial load operation. Determine the respective performance of different partial load conditions and weigh them.
Further information
0
25
50
75
100
Your data on the intended use of waste heat
Type of waste heat recovery:
Select a waste heat utilization (or a heat exchanger in the room air conditioning system module).
Note: When using heat pumps, additional power is required.
Further information
Fresh Air Heating
Service Water Heating
Heating/Heating Support
Process Heat
Absorption Refrigeration System
Power Generation: ORC Process
Power Generation: Steam Power Process
Simultaneous operation of waste heat source and waste heat recovery system (weeks / year):
Depending on the type of waste heat used, enter the number of weeks in which the available waste heat can be used.
For any heating support, the waste heat can only be used during the heating season for the building.
Further information
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
Cost estimates
Fuel price:
Gas: Net price per kWh (see invoice)
Fuel oil: 1 l of fuel oil contains approx. 10 kWh of energy => Net fuel oil price per liter (see fuel bill) divided by 10 gives the price to be entered per kWh.
Interest rate: interest rate to be paid on a loan
Payback Period: Time period within which the waste heat utilization facility is depreciated.
Further information
Fuel price (Euro / kWh):
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.11
0.12
0.13
0.15
0.17
0.19
0.21
0.23
Electricity rate (Euro/kWh):
The net electricity price incl. all charges, duties and electricity tax must be stated.
0.05
0.06
0.07
0.08
0.09
0.1
0.11
0.12
0.13
0.14
0.15
0.16
0.17
0.18
0.19
0.2
0.21
0.22
0.23
0.24
0.25
0.26
0.27
0.28
0.29
0.3
Interest per year (% / year):
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
8
9
10
12
Payback period (years):
2
3
4
5
6
8
10
12
15
20
