Electric car advocates like to split themselves into different groups. Hybrid vs. plug-in hybrid vs. battery vs. fuel cell. While it’s fun to joust about which is better, we should pause once in a while to reflect on how all of them are better for the environment than conventional cars with internal combustion engines. But if you really want to have the definitive answer to whether an electric car is more environmentally friendly than a fuel cell car, the folks at the Stanford University Global Climate and Energy Project say they have it.
“We looked at how large scale adoption of electric vehicles would affect total energy use in a community, for buildings as well as transportation,” says lead author Markus Felgenhauer, a doctoral candidate at the Technical University of Munich and former visiting scholar at Stanford. “We found that investing in all-electric battery vehicles is a more economical choice for reducing carbon dioxide emissions, primarily due to their lower cost and significantly higher energy efficiency.”
Why bother with such research? It’s about the environment, stupid. Sally Benson, professor of energy resources engineering at Stanford and director of GCEP says, “Studies such as these are needed to identify the lowest cost and most efficient pathways to deep decarbonization of the global energy system.”
Policymakers need to know which transportation technology cuts total emissions at the lowest cost—batteries or fuel cells? Beyond transportation, could hydrogen technology also provide clean energy for heating and lighting buildings, as some research suggests? The latest study by GCEP, published by Science Direct, finds that communities are better off investing in electric vehicles that run on batteries instead of hydrogen fuel cells. The reason? Hydrogen offers few additional energy benefits besides clean transportation.
The researchers focused on California, a leader in electric car adoption. It made various assumptions about a typical California community — Los Altos Hills — in the year 2035. One of those assumptions was that excess solar power would be used to power electrolyzers to make hydrogen from water by then and that the cost would be competitive with electricity from the grid.
“We provided data on the amount of energy Los Altos Hills needs throughout the day, as well as financial data on the cost of building new energy infrastructures,” says study coauthor Matthew Pellow, a former GCEP postdoctoral scholar now with the Electric Power Research Institute. “We included the cost of making solar panels, electrolyzers, batteries, and everything else. Then we told the model, given our scenario for 2035, tell us the most economical way to meet the total energy demand of the community.”
To compare each scenario’s costs to its climate benefits, the researchers also calculated the carbon dioxide emissions produced in each case and assessed the potential benefits of using the hydrogen infrastructure to store clean energy for use on demand. During daylight hours, electrolyzers can produce hydrogen from surplus solar power that would otherwise go to waste. That hydrogen can be stored and converted into renewable electricity, or used as a clean alternative to natural gas to heat and light buildings.
The results were definitive. “In terms of overall costs, we found that battery electric vehicles are better than fuel cell vehicles for reducing emissions,” Felgenhauer says. “The analysis showed that to be cost competitive, fuel cell vehicles would have to be priced much lower than battery vehicles.
“However, fuel cell vehicles are likely to be significantly more expensive than battery vehicles for the foreseeable future. Another supposed benefit of hydrogen—storing surplus solar energy—didn’t pan out in our analysis either. We found that in 2035, only a small amount of solar hydrogen storage would be used for heating and lighting buildings.”
While the study focused on one Bay Area town, the results are relevant for many bedroom communities with ample sunlight across California, the authors write. They hope to analyze larger networks of communities in future studies and examine other factors that could influence consumers choices when deciding whether to buy a battery or fuel cell car.
“Our goal is to provide objective, data-driven analysis to help inform policymakers in California and elsewhere about which technology pathway is likely to be more cost-effective in combating climate change,” Pellow says. The study was funded by GCEP and BMW Group.
Source: Stanford University