1. IEA-DSM Task XXI Expert meeting
Household Subsidy Programme – Norway Energy savings from residential heating technology deployment (ex.: heat pumps)
IEA-DSM Task XXI Expert meeting
Madrid, Oct 2010
Even Bjørnstad
Enova SF

2. Programme description
Heating of homes
High dependence on direct electrical heating
Subsidy for el. Saving heating technologies: 20 % - max €625
2003, >
Successful market development
How to measure savings?

3. Key methodological challenges:
Variation in heating need
Heating vs. non-heating electricity consumption
Accuracy of consumption data

4. { 1) Variation in heating needs (in time and space)
HDD = Heating Degree Days
Defines the normal year {
0 if t* ≥ 17 ˚C
HDD =
17 - t* otherwise
t* = avg. daily temp. in ˚C

5. 2) Heating vs. non-heating consumption
or: end use distribution
Necessary to identify heating part
Typically >60 % of household el consumption for heating
Alt 1: Explicitly calculate heating share
Alt 2: Heating share as residual after ”basic need”

6. 3) Consumption data
- Metered
- Biased by substitutions, rebound, etc?
- Based on survey

7. Parameters and variables
TC = total consumption of electric energy, kWh
HC = heating consumption of electric energy, kWh
NHC = non-heating consumption of electric energy, kWh
HDD = Heating Degree Days
N = index referring to a normal year
t = time (years) after installation.
t = 0: last year before installation, baseline year
t = 1: first year after installation
t = T: lifetime of the investment/installation
i = 1..n = household index/identifier.
n = number of households participating in the programme
k = number of members in the household
S = net (annual) savings, kWh
PS = programme savings, kWh
LS = lifetime savings
r = depreciation factor

8. Formulas

9. Calculation Calculated average saving per household: 6.121 kWh/year
Programme savings year 1:
6.121 kWh * households = 110 GWh
Programme savings year 7 – after market development:
6.121 kWh * appr households = 2,45 TWh

10. Discounting of energy result?
Q1) Should future programme results be ”diminshed”?
Q2) If yes, how?
Discounting:
or:
Depreciation: