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What are the likely total energy vectors of the future?

Hydrogen for grid-2-gas load balancing in future energy systems M E Crowther – General Manager GASTEC at CRE Ltd 15 th September 2011. What are the likely total energy vectors of the future?.

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What are the likely total energy vectors of the future?

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  1. Hydrogen for grid-2-gas load balancing in future energy systems M E Crowther – General ManagerGASTEC at CRE Ltd15th September 2011

  2. What are the likely total energy vectors of the future? • Electricity - expensive to deliver and effectively cannot be stored. Inter-seasonal storage the greatest challenge. • Biogas - tends to easiest derived from food competitive sources • Hot water - very expensive to deliver • Hydrogen - ???

  3. Recent hydrogen studies • Hyways - the EU-wide study on hydrogen powered road transport • & • NaturalHy - the EU-wide study on adding up to 50% hydrogen to distributed gas …have highlighted the safe and cost-effective nature of generating hydrogen.However, surely this is only part of the story?

  4. What next? If the UK is going to the trouble of introducing a network of hydrogen filling stations and/orAdding 50% hydrogen to Natural Gas (ie re-inventing Town’s Gas)Then surely it could be easier and cheaper to simply distribute 100% hydrogen?

  5. What next? Table showing the non-linear benefits of adding hydrogen at Natural Gas. Thus 20%v/v hydrogen (upper limit without full appliance conversion) only produces 8% reduction in carbon emissions

  6. The GaC concept Introduce conversion programmes to 100% hydrogen, piecemeal across the UK, using existing Local Distribution Zones to supply:- Existing Natural Gas users Road Transport Filling Stations  New uses of hydrogen in low carbon industries

  7. Where will the hydrogen come from? • We could derive the hydrogen from:- • Excess renewables • Wind • Wave • Solar PV • >83% eff HHV (photo) • Biomass via gasification • Biogas from Anaerobic Digestion

  8. Where else could the hydrogen come from? • From fossil fuel using Carbon Capture and Storage • Natural gas via reform & shift • Coal/Coke via gasification and shift • A true competitive free market can exist as hydrogen can be produced, • stored, traded and sold ‘at leisure’, similarly to oil or natural gas.

  9. So? I think we have established that there are several competitive routes to hydrogen.Additionally….….hydrogen solves ALL the problems of seasonality with a few simple storage caverns of modest dimensions.

  10. Change-over at the LDZ scale means…. • The transition can be carried out piecemeal – eg Bristol, or Newcastle • No ‘change of use’ will be necessary for the NTS • No disruption of international carriage of Natural Gas or supplies to existing power stations

  11. Householder choices • Householders can either use H2 boilers or Fuel Cells to generate their heat and power • Fuel cells close-coupled to heat pumps offer even more exciting opportunities

  12. Distribution To repeat, we are NOTsuggesting (at this stage) a national network of high pressure hydrogen lines….. ….because this is expensive and technically challenging. We are suggesting the re-purposing of the existing local natural gas distribution zones to hydrogen. The national (or even international) network well may arise but we are trying to emulate most historical fluid grids ie start small and interconnect latter.

  13. Distribution Whilst hydrogen has a CV of only 13,000kJ/m3 compared to 39,000 kJ/m3 for natural gas, it is 1/10th the density; so it is envisaged that with energy efficiency measures and local attention to system integrity, many existing PE grids will require little reinforcement.

  14. Distribution The Wobbe Number of methane and hydrogen are not that different:- So the system would require only a 10% uplift in capacity

  15. Distribution Each local hydrogen network would have its own storage facility for seasonal variants. It is suggested that Hydrogen has a ‘green’ footprint for long term energy storage if compared to water pump storage (flooded valleys) or exotic batteries (exotic metals).

  16. Distribution To convert an LDZ to hydrogen would require:- Its disconnection from the NTS Provision of H2 production facility Construction of local storage Pressure testing with hydrogen & confirmation of integrity Reinforcement of pipework capacity Replacement of meters and local appliances It is not a vast exercise compared to full electrification.

  17. The advantages To consider in detail the advantages of distributed hydrogen….

  18. The demand The UK gas plus electricity demand (minus gas to power stations) is strongly seasonal. Daily gas peaks can be even twice these values.

  19. The Finances • If this seasonal gas load were going to be replaced by electricity, it would require a massive (manifold 3 to 4.5) increase in electrical generation and distribution facilities, which would only be used very intermittently and to a frequency that it is extremely difficult to predict. • Very approximately, the cost ratio of distributing energy is as follows (where distribution includes fees for stand-by capacity etc):- • Natural Gas x pence/kWh (hydrogen will be similar) • Electricity 7x pence/kWh • Hot water 49x pence/kWh • This can be seen in current UK fuel costs (excluding billing)

  20. The Finances UK retail fuel cost 2011…indicative

  21. The Finances Further more what happens to the thermal efficiency of gas or coal plant with CCS when operated at steep ramp rates? To cope with peak electrical demands in an “all-electric” world, means building either…. • Coal + CCS at £3,000/kW or • a ‘surplus’ of wind turbines or • significant storage of currently unproven design. …which would only operate profitably for a few days/year; a deeply unattractive option!

  22. The Finances • If a high percentage of our electricity arises from :- • Wind at 30% availability • Tidal at widely swinging values (eg Severn barrage 8.2GW to zero, 4 times/day) • Then the situation becomes even more difficult. We also have to ask ourselves:- • Will the peak winter loads (eg long-lasting Siberian High) coincide with low wind speeds? What physical area would these ‘highs’ cover? and • What would be the true reliability of an EU supergrid? • Inter-seasonal storage of hydrogen solves all this.

  23. The Challenges • Hydrogen can be safely stored as demonstrated at:- • Billingham • In Germany, and more recently • By Praxair in Texas • By uncoupling supply and demand of/for hydrogen, a free market can exist in both.

  24. The Challenges The level of this uncoupling can be subject to debate. The author suggests about 3600kWh per person - ie about 95kg H2/person would suffice…. (try to imagine a cube of side 850m at 80barg for the whole of the UK!)

  25. At what price? Looking at some costs: let us say that hydrogen, costs 4.5p/kWh to generate (ref US data from Nat Gas +CCS) and is twice the price of Nat gas to distribute (including storage) (Prices 2011) We now have a ‘competitive zero carbon fuel’ ….….(well almost! And certainly competitive with projected future electricity costs, as these are bound to rise)

  26. At what price? Further US EIA data on projected hydrogen production costs;2008 Comparative UK energy transmission costs

  27. At what price?

  28. At what price? Possible ‘back-up’ costs of low carbon biomass electricity

  29. At what price?

  30. Other advantages By not taking carbon into the community we can immediately “know” the true extent of carbon saving.We are no longer dependent upon lifestyle choices.All static gas use is replaced with hydrogen use.Carbon savings must, therefore, be delivered.

  31. Transport The transport sector can be converted to hydrogen vehicles via the UK’s existing 9,000 garages.Advantages:- Refuelling pattern & hence lifestyle is the same as petrol & diesel Low cost hydrogen immediately available Do not need to store large quantities of HP hydrogen on site (only buffer quantities required)

  32. Industry New opportunities for the gas industry in new ‘low carbon’ heavy industries to replace coal and coke and take the UK to the ‘cutting edge’, as it was at the birth of the gas industry eg:-iron & steel glass refractories etc

  33. Safety Hydrogen:-NOT Toxic, Carcinogenic or RadioactiveIt has no military useDoes not leak significantly through walls of PE pipesDiffuses away more quickly than methaneDoes not embrittle steel below 25bargWas 50% v/v Town’s GasCan be carried safely through the existing gas networkBUT does leak more quickly though holes created by corrosion/3rd party damage and is flammable with a low ignition energy thus a full risk assessment of 100% hydrogen still needed.

  34. Widespread introduction of Fuel Cell CHP Both full scale CHP and mCHP save carbon right now in 2011 because of the high carbon intensity of UK electricity (typically 0.52kg/kWh) This situation is likely to last for several years, BUT as the grid is decarbonised (as must occur to meet Government policy) the net savings will decrease until, at an electrical grid intensity of about 0.22kg/kWh, even simple natural gas-fired CHP is carbon neutral.

  35. PEM fuel cells • Let us investigate the possibility of the widespread introduction of local PEM fuel fuels consuming hydrogen as a source of local heat and power. • PEM fuel cells:- • Simplest and most proven of fuel cell technology. • Operational temperature compatible with small scale heating systems. • Good electrical efficiency • Acceptable cost

  36. PEM fuel cells Ref University of Cambridge DoITPoMS

  37. Fuel Cells – how much? Fuel cell system costs have decreased significantly over the past several years, and although still nearly twice as high as those for internal combustion engines are falling fast Source: USDOE, Hydrogen Program Records 5005, 8002, 8019, and 9012 (http://www.hydrogen.energy.gov/program_records.html)

  38. At home? Indicative economics of a property purchasing hydrogen at 8.5p/kWh, and using a fuel cell microCHP or a condensing boiler (fuel cell heat efficiency is apparently modest due to the use of a boost burner)

  39. Other fuel cell options… • The possibilities of fuel cell plus heat pump are even more exciting! • Similar arguments can be advanced for the use of fuel cells in the transport sector.

  40. Pros/Cons of an all-electric approach:- • Electric Space heating:- • Resistance heating - simple but expensive • ASHP - simple installation, but annual efficiency less than GSHP (both of complex installation) • Requires substantial capacity in BOTH generation and transmission/distribution to meet winter peak. • Transport:- • Batteries are well proven, but can be heavy and are always likely to be of short range. • In other words, an expensive infrastructure with no strategic energy reserve.

  41. Pros/Cons of mixed hydrogen / electric approach with local fuel cells • Space heating:- • Simple compliance with winter peaks and no need to re-enforce local wires • Simple boiler replacement in the home with high temperature radiators • Uses much of local (ie – low pressure) natural gas infrastructure • Transport:- • Simple replacement of pumps at existing vehicle forecourts with compressed hydrogen units • In other words, modest cost infrastructure with simple strategic energy reserve.

  42. The future Let us not close our minds to the potential for hydrogen as an alternative low carbon energy vector.

  43. www.gastecuk.com enquiries@gastecuk.com +44 1242 677877 Thank you!

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