HYDROGEN AND FUEL CELLS:
A COMPREHENSIVE SOLUTION IN THE FIGHT AGAINST GLOBAL WARMING
May 16, 2007
By John Shears Research Coordinator
Center for Energy Efficiency and Renewable Technologies (CEERT) rd 1100 Eleventh Street * 3 Floor * Sacramento CA 95814 * (916) 442‐7785 www.ceert.org
HYDROGEN AND FUEL CELLS: A COMPREHENSIVE SOLUTION IN THE FIGHT AGAINST GLOBAL WARMING
INTRODUCTION The world’s leading climate experts have now declared that human activities — predominantly due to our use of fossil fuels 1 — are unequivocally accelerating global warming. They also warn that, in order to avoid the most devastating consequences of climate change, governments have to develop effective 2 policies to combat global warming within the next 1015 years. Some governments have responded with renewed urgency in developing and implementing policies while others are moving 3 more slowly. Electrical power generation and transportation are responsible for the bulk of the greenhouse gas (GHG) emissions from the use of fossil fuels. Transportation accounts for 2530% of the world’s greenhouse gas emissions of which 80% are from on 4 road transport. As such, transportation should represent a top priority for policy makers, who will be challenged with determining the best approach for reducing GHG emissions. One approach that is gaining wide acceptance in policy circles is to assign each economic sector responsible for generating GHG emissions their own respective “slice” of the global warming pie (i.e. their own emissions wedge). Then, governments can direct policies towards each sector, centered on available and soon to be commercialized technologies. The transportation “slice” can 5 be addressed by diverse approaches. The challenge for policy makers is “making the right set of choices” and harmonizing these different approaches into a comprehensive strategy. To help position hydrogen and fuel cells in the discussion, this discussionbrief provides an overview of some of the major approaches and the role that each can play in achieving maximum longterm GHG emissions reductions. OPTIONS TO REDUCE CARBON FOOTPRINT OF VEHICLES The diverse options being pursued to reduce GHGs from vehicles include low carbon biofuels; flexible fuel vehicles; compressed natural gas vehicles; hybrid electric vehicles (HEV); plugin hybrid electric vehicles (PHEV); allbattery electric vehicles (BEV or EV); and hydrogen fuel cell vehicles (FCV). Each has a role to play but only one appears poised to provide a comprehensive solution for the longterm stabilization and reduction of GHGs.
Modified From: Pacala,S. and R. Socolow, AUGUST 13, 2004. Stabilization Wedges: Solving the Climate Problem for the Next 50 Years with Current Technologies., Science Volume 305, pp 968972 (Part of the Special Section on the Hydrogen Economy).
Greenhouse Gas Emissions Wedges: A Slice of the Global Warming Pie.
(A) GHG emissions under business as usual (BAU – green area) are projected to double from 7 billion tons per year (GtC/y) today to 14 billion tons per year by midcentury. Climate scientists are urging that CO2 emissions must be stabilized if concentrations are not to exceed 500 ppm (blue area) in order to avoid dangerous climate change. (B) A schematic representation of (A). The increased emissions are represented as a triangle cut into 7 stabilization wedges. Each wedge represents a 1 billion ton (IGT) slice of potential annual emissions reductions. The suggested approach requires that policy be directed towards a reduction in GHG emissions from each of seven economic sectors. Hydrogen and fuel cells could contribute significantly in reducing emissions from the transportation sector.
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HYDROGEN AND FUEL CELLS: A COMPREHENSIVE SOLUTION IN THE FIGHT AGAINST GLOBAL WARMING
COMPARISON OF VEHICLE TECHNOLOGIES
Vehicle Technology Option Market Introduction & Timeline Well to Wheel GHG emissions reductions of Technology Option (Relative to a midsized car) Current Constraints / Limitations Maximum Total FleetWide GHG 6 Reductions.
E L E C T R I F I C A T I O N*
Fuel Cell Vehicle
2015 – 2050
30100% (Natural gas H2 – all renewable including biomass) 0100% (Coal fired electricity generation all renewable)
Range, battery size, weight & performance, cost, availability of nearzero GHG emission electricity from grid and grid expansion. Same as for battery all electric and challenges with all electric range
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