1. SINTEF Energy Research Emerging technologies for decarbonization of natural gas Dr. ing. Ola Maurstad

2. SINTEF Energy Research Outline of the presentation Emerging technologies Natural gas based power cycles with CO 2 capture Hydrogen production from natural gas Two energy chain calculations Gas to electricity Gas to hydrogen/transport

3. SINTEF Energy Research Decarbonization of natural gas: CO 2 capture and storage (CCS) CO 2 is a natural product of combustion of fossil fuels CCS is a strategy for reduction of greenhouse gas emissions CO 2 is captured at its source (power or hydrogen plant) Several storage options are being investigated depleted oil and gas reservoars geological structures etc Enhanced oil recovery (EOR) where CO 2 is used as pressure support This could give the CO 2 a sales value => would help market introduction of CCS technologies

4. SINTEF Energy Research The Sleipner project in the North sea (Norway) is the worlds first commercial-scale CO 2 capture and storage project (started 1996) 1 million tonnes are stored yearly in the Utsira formation 800 m below the sea bed Statoil: Storage capacity for all CO 2 emissions from European power stations for 600 years The project triggered by the Norwegian offshore CO 2 tax

5. SINTEF Energy Research Natural gas fired power plants with CO 2 capture Several concepts have been proposed Two concepts based on commercially available technology Post-combustion exhaust gas cleaning (amine absorption) Pre-combustion removal of CO 2 No plants have been built Could be built in 3-6 years from time of decision Cost of electricity increases with ~ 100 %

6. SINTEF Energy Research 1: Post-combustion principle 2: Pre-combustion principle 3: Oxy-fuel principle Principles of power plants with CO 2 capture

7. SINTEF Energy Research 65 SOFC+CO 2 capture Efficiency potential incl. CO 2 compression (2%-points) Year 123456789101112131415 Time until commercial plant in operation given massive efforts from t=0 43 45 47 49 51 53 55 57 59 61 63 Combined Cycle Post-combustion amin-absorption Pre-combustion, NG reforming Chemical Looping Combustion AZEP Oxy-fuel Combined Cycle

8. SINTEF Energy Research Example: Oxyfuel power cycle Fuel Pressurized oxygen To storage Water Water separator HRSG Compressor Turbine Heat Recycle Steam cycle Combustor 83% CO 2 15% H 2 O 1.8 % O 2 96% CO 2 2% H 2 O 2.1 % O 2

9. SINTEF Energy Research Natural gas reforming (NGR) Cheapest production method for large scale hydrogen production NGR is a commercially available technology Gas separation systems are also commercially available However, no NGR with CO 2 capture and storage exist Cost estimate for hydrogen production: Without CO 2 capture: 5.6 USD/GJ With CO 2 capture: 7 USD/GJ

10. SINTEF Energy Research Simplified process description, steam methane reforming (SMR) Reforming reaction (endothermic) : C m H n + mH 2 O = (m+½ n)H 2 + mCO Water gas shift reaction (slightly exothermic): CO + H 2 O = H 2 + CO 2

11. SINTEF Energy Research Hydrogen liquefaction Why liquefy hydrogen? LH 2 is suitable for transport to filling stations because of the high energy density: 2.36 kWh (LHV) per liter Petrol: 9.1 kWh (LHV) per liter Mature technology but improvements expected Theoretical minimum work required to liquefy 1 kg of hydrogen: 14.2 MJ Best large plants in the US require 36 MJ/kg H 2 Linde cycle

12. SINTEF Energy Research Ortho-Para conversion The two forms of dihydrogen: diatomic molecule Equilibrium composition depending on temperature Room temperature: normal hydrogen (25 % para, 75 % ortho) Liquid hydrogen temperature: nearly 100 % para Necessity to convert from ortho to para in the cycle Heat released by conversion at 20,4 K: Q conv = 525 J/g Latent heat: Q vap = 450 J/g Without conversion from ortho to para => In 24 h 18 % of the liquid will evoparate even in a perfect insulated tank (spontaneous, exothermic reaction from ortho to para)

13. SINTEF Energy Research Modified 2002 Toyota Prius: Hydrogen combustion engine + electric motor

14. SINTEF Energy Research The energy chains – Two examples 1.Gas fired power plant with CO 2 capture Energy product: 1 kWh electricity delivered to the grid 2.Large scale hydrogen production from natural gas with CO 2 capture – liquefaction of H 2 for transport to filling stations Energy product: 1 kWh liquid hydrogen (LHV) Energy product: 1 km of car transport

15. SINTEF Energy Research

16. Assumptions used for the energy chain analyses Power plant with CO 2 capture: 50 % (LHV) efficiency, 85 % capture of formed CO 2 Power plant without CO 2 capture: 58 % (LHV) efficiency Hydrogen production with CO 2 capture: 73 % (LHV) efficiency, 85 % capture of formed CO 2 Hydrogen production without CO 2 capture: 76 % (LHV) efficiency Hydrogen liquefaction 36 MJ electricity required per kg of liquid H 2

17. SINTEF Energy Research Hydrogen filling station Insignificant electricity consumption compared with the liquefaction process Hydrogen car Storage tank with H2 in liquid form Hydrogen consumption of 14.2* gram/ km (corresponds to a petrol consumption of 0.52 litres per 10 km) * Energy Conversion Devices claims their modified Toyota Prius can drive 44 miles per kg hydrogen ( http://www.hfcletter.com/letter/December03/features.html)

18. SINTEF Energy Research Results: Power generation

19. SINTEF Energy Research Results: Hydrogen production (natural gas to liquid hydrogen)

20. SINTEF Energy Research Results: Hydrogen production (natural gas to transport product)

21. SINTEF Energy Research Conclusions CO 2 Capture and storage (CCS) technologies can reduce the emissions of CO 2 by 80-100 % per unit electricity or H 2 In general, the capture and storage processes impose an energy penalty on efficiency of around 2-10 %-points Estimate of the added costs today (technologies closest to commercialization): - Cost of electricity: ~ 100 % increase - Cost of hydrogen: ~ 30 % increase The costs will always be higher with CO 2 capture => Markets for CCS technologies will not be developed without government policies (economic incentives)

22. SINTEF Energy Research Thank you for your attention!