This document summarizes the results of a study by the Danish Energy Agency on achieving 100% renewable energy in Denmark by 2050. It considers various scenarios - Wind, Bio+, Biomass, Hydrogen - that rely on different combinations of wind, solar, bioenergy, and hydrogen. All scenarios require large increases in energy efficiency and electrification. The Wind and Hydrogen scenarios are fuel secure but challenge electricity grid stability, while the Bio+ scenario challenges fuel sustainability but has higher grid stability. Transitioning to 100% renewable energy will require investments that increase costs 5-23% compared to fossil fuels but must begin shortly after 2020. Security of supply will rely on flexible demand, heat storage, reserve capacity and electricity markets.

1. Fossil-free Scenarios for a
Danish Energy System 2050
Model and Results.”
Sigurd Lauge Pedersen
Danish Energy Agency
www.ens.dk
17-11-2014

2. Political background
 A broad majority in the Parliament
behind the development to 2020
(Agreement March 2012).
 Government target: Fossil-free
electricity and heat production by
2035 (and no coal in power plants
by 2030).
 Parliament supports 100 % RE in
2050 and EU 2050 target.
 Nuclear ban from 1985.

3. 3
0
300
600
900
1990 '95 '00 '05 '10 '12
PJ
Oil Natural gas Coal and coke Renewable energy etc.
Where are we now?
Gross energy consumption by fuel

4. Short term transition
Danish electricity production
3 large offshore wind parks + near-coastal offhore parks.
A number of coal-to-biomass conversions on power plants.
Solar PV 2,7 % by 2020.

5. Design criteria for 100 % RE
• Wind and solar
abundant.
• Bio-energy limited.
• Total bio-energy is
chosen as the
primary design
criterion.
• Energy savings and
wind/PV will have
to deliver the rest.

6. 2050
scenarios
 Wind: Bioenergy ≈ Danish ressources.
 Bio+: Coal/oil/gas replaced by bioenergi.
 Biomass: A compromise.
 Hydrogen: Minimizes biomass.
 Fossil: For comparison (not BAU).
Large energy savings in all scenarios.
Massive electrification in Wind and
Hydrogen scenarios. Moderate in Biomass
and Fossil Scenarios.

7. Methododology and assumptions
• Energy demand model (energy quality;
economic growth + energy savings).
• EBM (bottom-up Energy Balance Model
with hour simulations).
• Technology costs and efficiencies from
4 technology catalogues.
• Fuel/CO2 prices: WEO (NP) + ETP (4o).
 Refineries in Denmark.
 Gas grid maintained (for green gas).
 Electricity storage: ”the market”.

8. Electricity grid
Gas grid
District heating grids
CHP
HP/EB
Refinery
Boiler
Engine
Space heat
Process
heat
Kin.energy
Electricity
Storage
Storage
Market

9. EBM (simulation model)
 Minimizes total cost
o ∑iElProdi(t) - ∑iFlexElDemandi(t) =
FixedElDemand(t)
o ∑iHeatProdi(t) = HeatDemand(t)  sectors
o ElProdi(t)  ElCapi
o HeatProdi(t)  HeatCapi
Electricity exchange: Price interface
Exogenous investments
+Monte Carlo simulations to verify security
of supply.

18. Security of supply.
• There appears to be a
choice between two evils:
 A: Use a lot of bioenergy
=> import dependence
and sustainability issues.
 B: Use very little
bioenergy => Challenges
electric security of supply.
Solutions: Flexible
demand + heat storage,
reserve capacity,
geographical +
technological dispersion
and electricity markets.

20. Hydrogen scenario
Wind scenario
Biomass scenario
Bio+scenario

21. Conclusions
• Various 100 % RE systems are possible using
”known” technology.
• Electrification, EE & savings are ”no regrets”.
• Wind and hydrogen scenarios: Fuel secure –
but challenged on security of electricity
supply.
• Bio+scenario: challenged on fuel safety –
higher ”national” security of electricity supply.
• Additional costs 5-23% relative to a fossil
system.
• The transition must begin shortly after 2020.

22. Thank you for your attention
http://www.ens.dk/sites/ens.dk/files/dokum
enter/publikationer/downloads/energiscena
rier_-_analyse_2014_web.pdf