Waste Not, Want Not: Maximizing Efficiency is Key to Decarbonization - Honolulu Civil Beat

About the Authors

Noel Morin

Noel Morin is a civic leader and environmental advocate. He is with Citizens’ Climate Lobby Hawaii.

Tam Hunt

Tam Hunt is a lawyer and activist based on the Big Island. He is co-founder of Think B.I.G. and a board member for the Hawaii Electric Vehicle association.

Improving energy efficiency is one of the easiest and most cost-effective actions that can be taken to reduce global-warming emissions. Increasing efficiency reduces our need for electricity, liquid fuels and gas. It reduces our dependence on oil imports and, importantly, reduces living costs for regular people.

In Hawaii, generous rebates are offered to residents and businesses to encourage the replacement of inefficient appliances, light bulbs, water heaters, and other devices with more energy-efficient ones. This has allowed residents and businesses to reduce their energy consumption and save money.

We can achieve similar results when we optimize the efficiency of our largest ‘appliance’ – our cars. Hawaii’s cars and the rest of our transportation sector account for more than 60% of our greenhouse gas emissions. We burn around 30 million gallons of gasoline every month. And most of this energy is wasted due to serious inefficiencies associated with gasoline and diesel engines.

Many improvements are straightforward and apply to all vehicles, like removing unneeded items from the trunk, driving at appropriate speeds and maintaining tire pressure. These actions help reduce the amount of fuel required to operate the cars and reduce costs and emissions. Other actions, like switching from a gas-powered vehicle to an electric vehicle, can have far bigger impacts.

Afternoon commuters head west on the H1 freeway.
One step toward reducing energy consumption and saving money is to optimize the efficiency of our largest ‘appliance’ – our cars. Cory Lum/Civil Beat/2021

Buy The Most Efficient Car

There is a wide array of car options today – internal combustion (gas and diesel), hybrid, plug-in hybrid, fuel-cell electric and battery electric.

The most inefficient vehicles are traditional cars with an internal combustion engine. Only 12%-30% of the energy in the fuel used in these cars is used for propulsion. The rest is wasted as heat – around 80% of the energy. Put another way – for every $100 of gasoline, only $12 to $30 of that amount is used to move you around. The rest is wasted.

Hybrids are incrementally better, with the best models achieving about twice the efficiency of a regular car. Hybrids have, in addition to the regular engine, a battery and electric motor to enhance efficiency.

However, the most efficient vehicles are electric, which can be up to five times more efficient than a regular car. There are currently three types of electric vehicles:

  • Plug-in Hybrid Electric Vehicles (PHEVs) – electric vehicles that still require fossil fuel – these cars offer limited pure-electric miles and rely on a gas engine to keep the battery charged. Examples include the Kia Niro PHEV, Ford Escape, Honda Clarity, Toyota Prius Prime, and Kia Sorento.
  • Fuel Cell Electric Vehicles (FCEVs or “hydrogen vehicles”) – electric vehicles that rely on a fuel-cell to convert hydrogen to electricity. These vehicles include a small battery. Examples include the Toyota Mirai, Honda Clarity, and the Hyundai NEXO.
  • Battery Electric Vehicles (BEVs) – the ‘pure’ electric vehicle. These cars include a large battery to store the energy required for long-range driving and rely only on electricity for fuel. BEVs represent the vast majority of EVs on the road today. There is a growing number of EV makes and models — over a hundred will be available by 2023. And BEVs enjoy a steadily growing charging infrastructure and service options. Thanks to ever-evolving battery technology, BEVs are becoming more affordable over time and less reliant on rare metals like cobalt. Examples are Tesla (several models), Chevy Bolt, Nissan LEAF, Kia Niro EV, Ford Mach-e, and the recently-released Rivian R1T.

The BEV is by far the most efficient of these three types of EVs with roughly 73% efficiency versus 22% for the FCEV. The comparisons are summarized well in the first two columns in the following diagram from the nonprofit Transport and Environment’s 2017 report.

Many other reports and peer-reviewed publications have found similar results.

car battery graf for Noel Morin CV Dec 2021

The more significant losses associated with FCEVs are mainly due to the inefficiencies related to converting electricity to hydrogen, compression and transportation of the gas, and conversion of the hydrogen back to electricity. The losses are inherently due to basic physics.

A simple way to understand the efficiency differences between BEVs and FCEVs is to compare how far they travel on the same amount of electricity. For a given amount of electricity, a BEV will travel 300 miles for every 100 miles that an FCEV will travel.

The ‘Fueling’ Dilemma

It’s worth noting that around 97% of the hydrogen produced globally comes from methane or coal. Hawaii’s efforts in this space have, thankfully, been mainly focused on green hydrogen produced through mainly renewable energy. The above comparisons are relevant to FCEVs running on green hydrogen.

This is not to suggest that hydrogen vehicles or the fuel-cell platform are not valuable. Despite their inefficiency, they are valuable in applications where heavy transport is needed and gross vehicle weight must be managed, such as transoceanic air transport and possibly long-distance land and ocean freight. The fuel-cell can also offer a compact grid long-term energy storage solution.

Fueling BEVs and FCEVs can be a challenge. BEVs are still at an advantage here. BEVs can be fueled wherever there is an electrical outlet, and many EV owners rely on home charging for most or all of their charging. However, many people, renters, for example, may not have the opportunity to charge at home, so we need to dramatically expand charging infrastructure to support electric car and bus charging.

Hydrogen fueling is virtually nonexistent at this time. There are a couple of fueling stations on Oahu, including one that offers subsidized fueling for Toyota Mirai EVs. On Hawaii Island, a substantial hydrogen production facility exists at NELHA; a smaller one can be found at Blue Planet Energy near Puu Waa Waa.

The NELHA facility will generate hydrogen for three small buses as part of a demonstration project on Hawaii Island. Notably, a hydrogen fueling infrastructure is costly to deploy and dependent on electricity, which is also expensive.

Time Is Running Out

Hawaii has a tremendous opportunity to decarbonize its economy with renewable energy derived from solar, wind, hydro, and geothermal and sustainable transportation. A thoughtful transition of its ground transportation system from one mainly reliant on the passenger car to one that is multimodal (mass transit, micro-mobility, shared transportation) is critical.

A sustainable transportation future maximizes overall efficiency, which means reducing our collective vehicle miles traveled. Minimizing the need for cars is one meaningful way to accomplish this.

Since passenger cars will continue to be relevant, we also need to focus on the most efficient electric vehicles, those readily available, and those that can be serviced and fueled today. Hawaii is making progress on the vehicle electrification front – it is now number two in the nation in EVs per capita. However, EVs still represent only about 2% of the passenger vehicles in Hawaii.

We don’t have much time to achieve the emissions reductions required to contribute to meaningful climate change mitigation. By focusing attention and resources on solutions that are efficient and have the highest likelihood of success today, we can accelerate our transition away from fossil fuels. BEVs are the solution that will allow Hawaii to rapidly decarbonize its ground transportation, maximize its renewable energy, save money, and democratize clean transportation, 

Let’s mobilize our limited resources and focus attention on battery electric vehicles, a sure bet for sustainable transportation in Hawaii. We still have time to heal our planet and ensure a livable world for our keiki and future generations, but we must act with urgency.

Community Voices aims to encourage broad discussion on many topics of community interest. It’s kind of a cross between Letters to the Editor and op-eds. This is your space to talk about important issues or interesting people who are making a difference in our world. Column lengths should be no more than 800 words and we need a photo of the author and a bio. We welcome video commentary and other multimedia formats. Send to news@civilbeat.org. The opinions and information expressed in Community Voices are solely those of the authors and not Civil Beat.

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About the Authors

Noel Morin

Noel Morin is a civic leader and environmental advocate. He is with Citizens’ Climate Lobby Hawaii.

Tam Hunt

Tam Hunt is a lawyer and activist based on the Big Island. He is co-founder of Think B.I.G. and a board member for the Hawaii Electric Vehicle association.

Latest Comments (0)

People all say this while buying trucks that give far less fuel economy than smaller cars.  Hypocrites at best.  Imagine that, people who drive solo to work using trucks that get 18-25 MPG could be driving smaller cars that get 35-40 MPG (25% more efficient use of fuel).  Wow.  Maybe we should just raise the gas tax to encourage people to use more efficient cars?Seriously people think about it?  Yeah, the American way is all about image and prestige. Not about efficiency and productivity. Look at what our companies are doing with Planned Obsolescence?  Creating products that have limited lifespans, not durability just so they can sell more units for more profits......Greed at its finest while destroying the environment we live in...

jaytee777 · 1 year ago

Aloha, I don't doubt the author's desire for real climate action, but their conclusion that somehow All battery EVs are more efficient than Green Hydrogen Fuel Cell EVs, is upside down.  The authors are basing their conclusion on the World Bank graphic, however, the World Bank is notorious for ignoring some important aspects, including CapEx, OpEx, and external grid upgrades required for Battery EV infrastructure.  The biggest problem is the graphic ignores "Capacity Factor."  The Green Hydrogen FC example uses 100% of renewable energy to make clean hydrogen available for fleet use 24/7, with fast fueling and long range.  The BEV example can't do that.  In reality, BEVs are only plugged in around 12% of the time.  If 20% of the BEV fleet charges in a given day, what happens to the excess 80% of the renewable energy?  Use it, or lose it.  By ignoring 'Capacity Factor,' (how often the resource is used) the World Bank claim of 73% for BEV is vastly overstated.  Applying a 0.12 capacity factor, the actual efficiency (in the configuration proposed) becomes only 8.7% in the real world.  Correcting for this one oversight, yields the exact opposite conclusion the author's claim.  Aloha.

GreenHydrogenMag · 1 year ago

I appreciate the informative article. I concur with most of your conclusions. What caught my eye most though, is that I never realized that Oahu has a 7 lane highway on it. I don't know if I have ever seen a 7 lane Highway... that's 14 total Lanes! I came from California years ago and I never saw seven lane Highways.

Scotty_Poppins · 1 year ago

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