natural_gas_electric_vehicles
The following Questions & Answers relate to a recent guest blog post: Natural Gas and Twilight for the Combustion Engine that I wrote for Sustainable America:
Why not just improve the combustion engine?
It is natural for incumbents in the automotive sector to embrace incremental innovations on the combustion engine. In a recent survey of automotive industry engineers, improving the engine along with lighter composite vehicle chassis – were listed as top priorities. Other engineers see it as the wrong problem to solve – akin to the historical analogy of trying to build a faster horse versus abandoning the horse-buggy platform entirely and leaping into the risky, expensive mechanical age. Improving the engine’s efficiency does little to solve structural problems around design limitations and supply chain complexities.
The right problem to solve is finding a scalable, modular propulsion platform that can meet various needs in the global marketplace – and also align that platform with the digital / software revolution of the connected car.
The transition will take years to gain momentum, but eventually the cost structure of EVs and performance advantages of related drive-by-wire systems will approach a tipping point over mechanical systems. Suppliers such as Delphi have publicly stated their self-interest to accelerate adoption of electrification. The tipping point is debatable but history of technology platform transitions suggests that when 20% of new vehicle sales are electric we will see an acceleration of a more rapid transition as competition drives adoption. If we imagine multiple paths it is possible that the disruptive innovations will likely come from non-consumer industries (e.g. materials handling; private fleets – and then mainstream consumers). If you want to monitor some potential disruptive companies – Trexa, Local Motors, and River Simple are a few to watch.
Why wait for fuel cells when batteries are ready now?
Automotive industry leaders are seeking a solution that fits a key metric: cost-to-mass. This logical balance on the cost and weight leads to an integration of storage and fuel conversion devices.
Despite being a more mature commercial product, batteries for electric vehicles are not ready for prime time in cost-to-mass performance. There is no doubt that battery technology will continue to improve especially around the evolution of nanostructured catalysts – but as a storage device it will always have a higher weight issue compared to fuel cells.
Fuel cells offer many advantages. It is a solid-state energy conversion device that is twice as efficient as the combustion conversion of chemical bonds because is uses (non-combustion) electrochemical. This means that it takes the energy stored in chemical bonds and converts them into electricity, heat and water in a single step. Fuel cells are power plants. Design parameters will always evolve but you can imagine their size to be ¼ to 1/10th that of an equivalent battery pack.
The transition to electric vehicles will take years and decades to unfold. Battery-powered EVs will find their position in early markets, but it is unlikely that they will be alone as cost-to-mass imperatives favor integration with molecule fuel conversion devices.
Where are fuel cells today?
Today’s fuel cell industry is in its early stage of commercialization. Pikes Research expects the global fuel cell market to reach $17B by 2017 driven primarily by stationary applications. They key milestone for vehicle-based fuel cell applications is widely seen as $50/kW – which would bring it to parity with the combustion engine. A recent report by the US Department National Renewable Energy Laboratory (NREL) suggests rapid development of fuel cell electric vehicles. The idea of a fuel based electric vehicle is reinforced with stated plans by Toyota, Daimler, Hyundai whom have targeted 2015 for their first low volume FCEV production.
Bullish advocates of fuel cells point to the cost structure of fuel cell components and the untapped opportunities in nanostructured materials engineering to dramatically reduce costs and improve performance. Nanostructured materials hold promise in reducing the amount reducing the amount of precious metals such as platinum needed in fuel cell stacks; as well as better catalysts (often carbon+metal bonds) to help with oxygen side reactions and management of heat and water byproducts.
What is wrong with battery powered electric vehicles?
There is a long list of structural challenges to batteries: high cost-to-mass ratio, structural degradation, long charge times, thermal management, et al. There are also concerns about the inability to make profits from recharging infrastructure compared to the return on capital of molecule fuel based refueling stations.
Current efforts to improve batteries for vehicle systems will certainly improve – and we can imagine a wide range of battery powered electric vehicles making it to market in the next twenty years. In the near term, the most logical customers for plug-in electric vehicles are large vehicle fleet owners who can establish clear usage patterns that justify costs of infrastructure and operational support. But most signals from the automotive industry suggest the end game will likely integrate batteries alongside fuel cells to deliver electricity.
But we already have infrastructure for Electric Vehicles?
The idea that we can tap existing electricity grid for vehicles is greatly overstated. Yes, we have a complex network of wires and wall sockets – but it is not adequate for integration of vehicles. Utilities operate within a highly regulated market and it is difficult to imagine a business case for capital investment on recharging infrastructure that does not provide a clear, fast path of return on investment.
There are private sector developers such as Better Place and Charge Point vying for market share in early adoption markets such as Israel, Denmark, and states such as California . Many of these companies are building business model around subscription to network access, but analysts continue to show concern around the lack of profit margin in delivering low cost electrons to cars that need long access times at charging facilities.
Building molecule fuel infrastructure for electric vehicle will be expensive – but also offer a faster road to recovery of capital when compared to recharging stations.
Why not use natural gas for combustion engine?
There are certain situations where compressed natural gas (CNG) vehicles are appealing to fleet owners looking to save on fuel costs compared to gasoline and diesel. The challenge of moving beyond fleets into mainstream consumer cars is that CNG must then compete directly against the incumbent oil marketplace.
On the manufacturing side, CNG vehicles that use combustion engine technology only add costs to automobile makers and do little to address structural limitations of global growth on this mechanical engine platform.
Isn’t electricity cheaper than hydrogen-rich fuels?
While plug-in advocates cheer the low cost of recharging, industry insiders are puzzled and many producers believe it is too cheap to support a sustainable business model. There are significant capital and operational costs associated with delivery electrons to end users — and when the consumer pays pennies to recharge their vehicle – it leaves the producers with a profit gap and a non-sustainable business model. Extending the electricity grid a final few feet to end users is not cheap and likely not profitable. The molecule fuel business provides a more sustainable revenue stream for producers to meet demand.
How efficient is it to convert Natural Gas to Hydrogen?
There is no easy answer because the difference between theoretical (80%) vs real world conversion (40-50%). It would be misleading to make any long term forecasts based on current materials science and engineering capabilities. The world is moving towards the functionalization of nanomaterials that can be used in more efficient conversion of natural gas to hydrogen. Reasonable forecasts will expect the efficiency of conversion to improve over time. At the same time, nanostructured materials will help reduce costs of electrolysis and other competitors to natural gas.