Hydrogen economy and nuclear energy

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					    Novi izvori energije
      Prof.dr.Vladimir Knapp

   Poslijediplomska predavanja
Fakultet elektrotehnike i računarstva

Hydrogen economy and nuclear energy

A discussion on the future of the so called
hydrogen economy and its relationship to
             nuclear energy

        Conclusion of discussion
    (I hope to convince you by what
    If hydrogen economy, then with
           nuclear hydrogen                   2
    No lack of the initiatives on hydrogen,
              some recent ones:
• US: Nuclear Hydrogen Initiative
• International Partnership on Hydrogen Economy
• IEA: Hydrogen Coordination Group(2003)
• EC: European Hydrogen and Fuel Cell
Arguments for hydrogen introduction on the large

    Arguments for introduction of hydrogen
Clean fuel, no CO2 emission from fuel cells or in combustion

   Use of hydrogen can therefore help in:

• Reduction of local air pollution
  Primarily in transportation, by replacing standard fuels
  with hydrogen for fuel cells or for hydrogen ICE
      (2 H2 +O2 = 2 H20)
• Reduction of global emission of CO2
  Achieved by hydrogen use in transportation, providing
  hydrogen is produced from non-fossil energy

To see this in perspective let us look first at the global energy
                World energy outlooks
  70% increase of world energy consumption between 2000
  and 2030. This means a modest 1.8% average annual
  increase. Inadequate to remove the development gap
  between rich and poor countries. Contribution of nuclear
  and renewables 13% in 2030. Sources:

• IEA-World Energy Outlook 2002 (WEO):
• WETO-World Energy , Technology and Climate Policy
   Similar projections, contribution from nuclear and
  renewables in 2030 12%. Fossil fuels expected to cover
  90% of the increase up to 2030.What would follow from
  such projections is doubling of Co2 emission from 1990 to
  2030, from 21 to 45 Gt of CO2.                          5
Very important step forward is the ratification of Kyoto
protocol by Russian Federation. Document was signed by
President Putin, November 2004, after its ratification by
Russian Duma. Kyoto protocol from December 1997, as of
February 2002 was ratified by 104 countries (not yet by
Croatia), representing 43.9% of emissions. According the
terms of the Treaty it enters into force 90 days after at least 55
parties to the Convention, responsible for at least 55% of
emissions have deposited their documents of ratification or

Latest development in Kyoto convention:

Whilst the first conditon has long been fullfiled, by Russian
ratification also the 55% emission condition is satisfied,
meaning that Kyoto Convention will enter in force in March
2005. Then it becomes obligatory amongst the signatory
states. In December 2002 15 countries of EC created a
system of emission trading to meet the 8% reduction target by
2008. Fines are foreseen for member countries failing to meet
their obligations. Kyoto protocol has not been ratified by US,
which is one of the major international issues.

Kyoto limits are now important element of energy strategy

• Taking the necessity to reduce CO2
  emission seriously, hydrogen for hydrogen
  economy should be produced by non-fossil
  energy. This is the most important point in
  considerations of hydrogen economy. To
  see how and where, we must have a look at
  the structure of energy consumption:

 Structure of Primary Energy Consumption

  World:                       F  N
• Electricity production 33% (27%+7%)
• Industry and heating 34%
• Transportation         33%
  Europe:                     F   N
  Electricity production     (65%+35%)
Now closer look at European situation:

           Emission problems : EC situation
                                 (Data IEA)

    EU-15 emission of GHG was in 2000 equiv. 4059 Mt of CO2 ( With
    35% of nuclear electricity estimated emission saving is about 450 Mt
    of CO2). Going to 70% of nuclear share in electricity production
    would bring another similar reduction and so allow EC to reach the
    Kyoto reduction target for 2012 of 8%, assuming there is no increase
    of energy consumption in absolute terms.
     However, to both observe the Kyoto limit and to follow the projected
       energy growths, is possible only if non-fossil energy contributes in
          other two primary energy sectors, i.e., in industrial uses and in
        transportation. Hydrogen produced with fossil energy would only
     aggravate global situation, even if fossil energy hydrogen could be of
                  interest to relieve the local pollution problems.
    Now for the closer look on the effects of hydrogen use in

Some figures on hydrogen fuel economy

• Electrolysis uses 50 kWh/kg H2; with 3.5c/kWh of nuclear electricity,
   production cost per kg of hydrogen would be 1.75 USD (no taxes)
• Fuel cell car consumption 0.75 kg/100km = 1.3 USD/100km
• Standard car consumption 5-7kg/100km. Taking fuel cost without
   taxes at 0.4 USD/kg, fuel cost would be 2- 2.8 USD/100km
  Comparison of bare fuel costs shows advantage of hydrogen relative to
   standard car, however hybrid drives with petrol or diesel oil can reduce
   consumption to bellow 2 kg/100km and the fuel costs below
    1 USD/100km.
  ( For example Daihatsu UFE2, presented in Tokyo last year)

                  Some emission figures

• Fuel cell car is zero emission vehicle (ZEV) locally, not so in complete
  fuel cycle.
• Consumption of 0.75 kg H2/100km is equivalent to 37.5 kWh/100km
  with electrolysis hydrogen. If electricity is produced from coal, with
  thermodynamic efficiency of 1/3, this requires 13.8 kg of standard
  coal, whilst the amount of CO2 produced is 45.3 kg/100km
  Figure is shocking, admittedly coal use is the worst scenario. We take
  it, as, unlike gas, coal is the fossil fuel available in the long run..
• In the same time, best, but existing, petrol hybrid car with consumption
  of 2kg/100km would emit about 6 kg of CO2 per 100km

    Clearly, unless electricity for hydrogen production be nuclear, use of
   hydrogen in transportation would be very counterproductive regarding
   the CO2 emission.
       Dangerous competition in ZEV field
            Some illustrative figures
• Instead of using 37 kWh required to produce hydrogen, to supply
  hydrogen fuel cell car for 100 km, we could use the electric energy
  directly, to charge the batteries of electric car.
• With 40% charging and discharging loss, about 20 kWh would remain
  at the wheels. How far would this take us ?
• New petrol or diesel hybrids use about 2kg/100km
• Assuming fuel to wheels conversion efficiency of 1/3, propulsion of
  such car uses about 9 kWh/100km.
• Allowing that battery weight could increase consumption, electric
  ZEV with 20 kWh would take us twice the distance.
• Of course, for global CO2 reduction, electricity should be nuclear in
  this case as well.

 Hydrogen and global CO2                    emission

– The ultimate problem in future world energy strategy is how to
  prevent projected increase (WEO) in CO2 emission from 21 Gt in
  1990 to 45 Gt in 2030.

– No proposal how to do it! On thing is certain, to achieve this
  nuclear contribution would be needed in all three sectors of
  primary energy use.The size of the problem can be understood by
  assuming nuclear contribution to be on the global level equal to
  modest 17% (as is today in electricity sector) in all three sectors of
  primary energy consumption. This would require approximately
  tripling the number of reactors, respectively, adding some 800-900
  to the existing 440. With at present prevalent NIMBY public
  attitude this is difficult to imagine. Here the nuclear hydrogen may
  offer a way out.

         Advantages of nuclear hydrogen

• Global CO2 problem can be relieved only by non-fossil
  energy sources, nuclear or alternatives, where the nuclear
  contribution appears more realistic.
• Faced with continuing public NIMBY attitude, nuclear
  contribution via nuclear hydrogen may be more acceptable,
  by locating hydrogen production at few remote sites where
  from hydrogen would be shipped to users.
• Few remote sites would ease the control of proliferation
  sensitive nuclear installations collocated at these sites.
  This point will be of increasing importance as the nuclear
  energy is further developed and more widely distributed.

                Concluding remarks

– Nuclear hydrogen can help to diversify use of nuclear energy,
  especially in transportation.
– With many difficult hurdles to overcome on the way to hydrogen
  economy, these efforts would be difficult to justify unless
  hydrogen economy had a positive effect on CO2 control, which is
  possible only with non-fossil hydrogen.
– At present one cannot be sure that hydrogen economy will
  develop. What is, however, sure is that only nuclear hydrogen can
  be justified from the environmental point of view.
– Remote production of nuclear hydrogen could accommodate some
  public concerns and could offer an increase of proliferation safety
  over direct use of nuclear electricity.
– Nuclear hydrogen production would require high temperature
  reactors, indicating one important direction to nuclear reactor

• Lecture attempts to put a perspective on the
  hydrogen economy and its relationship to nuclear
• It argues that only hydrogen economy with non-
  fossil, de facto nuclear, hydrogen is
  environmentally justified.
• It points to one advantage of hydrogen economy :
  possibility of hydrogen production at few remote
  production sites.

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