Monday, February 9, 2015

Green Vehicle Choices

Being only an average thinker, and not a technical genius, I've had a great deal of trouble understanding the greenest options in modern automobiles. Automobile manufacturers are delivering better fuel economy and lower emissions intended to defeat climate change and improve their bottom lines. For simpletons like me, that means the technology has surpassed either my capacity to understand it, or my patience to study it—
Vokswagen Jetta Sportwagen TDI
or both. And, when you add advertising hyperbole on top of that…


The simplest hierarchy seems to be: conventional gasoline engines are the dirtiest with the worst fuel economy; followed by modern, clean diesel engines like the Volkswagen Jetta Sportswagen TDI ; then hybrids like the Toyota Prius and the Honda Insight are supposed to be the cleanest and leanest. Of course, the comparisons are muddled by new gasoline engines that are sippers like the Ford Focus SFE and the Honda Civic HF (both rate 40 mpg on the highway) in the same miles-per-gallon class as the TDIs of Volkswagen and Audi (a VW subsidiary)--  and further muddled by the Volkswagen Golf GTE diesel plug-in hybrid which can achieve 130+ mpg for 30 miles before it runs out of juice. 

Given the trade-offs of range, price and practicality, it seems that the conscientious tree-hugging buyer can find a green vehicle— at least in terms of fuel economy. Then comes the environmental impact of manufacturing, delivering and recycling its parts— particularly the robust batteries of hybrids and all-electric vehicles. 

A Sour Note on Batteries

The good news is that hybrid vehicles can reduce air emissions of smog-forming pollutants by up to 90% and cut carbon dioxide emissions by 50%. The bad news is that although more environmentally friendly than lead-based batteries, the two types of batteries primarily used by today’s hybrids, nickel metal hydride and lithium ion, present their own dangers—
Toyota Prius
and they are much, much larger than conventional car batteries. There are also questions about the economic viability of manufacturing the batteries in the long term. 


Nickel Metal Hydride (NiMH) Batteries
An older technology, NiMH has two major advantages over lithium ion batteries— price and safety. Nickel batteries are mildly toxic in that various nickel compounds, such as nickel chloride and nickel oxide, have known carcinogenic effects in chick embryos and rats. Some manufacturers of hybrid vehicles claim that NiMH costs one-third of an equivalent Li-ion system due to more relaxed safety rules.

An unfortunate disadvantage of NiMH batteries is their high rate of self-discharge. They lose about 20% of their capacity within the first 24 hours, and 10% per month thereafter. In 2005, a low self-discharge (LSD) technology was developed. LSD NiMH batteries significantly improve self-discharge, but have a capacity approximately 20% lower. NiMH batteries face other obstacles as well.

Stanford R. Ovshinsky invented and patented an improved NiMH battery and founded Ovonic Battery Company in 1982. General Motors purchased their patents in 1994, and by
Stanford Ovshinsky
the late 1990s, NiMH batteries were successfully powering many fully electric vehicles, such as the General Motors EV1 and Dodge Caravan EPIC minivan. 


But, in October 2000, the patent was sold to Texaco who was acquired by Chevron a week later. Chevron's Cobasys subsidiary chose to provide these batteries to large original equipment manufacturers (OEMs) only, for fleet vehicles and leases. General Motors shut down production of the EV1 citing lack of battery availability as one of their chief obstacles, but there is reason to believe GM bailed out for a variety of reasons—  including the potential decline of their lucrative spare parts business. Electric vehicles require fewer parts. 

Large-format NiMH batteries were, at that time,  deemed commercially viable and ready for mass production, but there is evidence to support that Chevron and other oil industry allies, even OEMs, may have suppressed the technology. In an interview with the Economist, Stan Ovshinsky stated, "I think we at ECD  made a mistake of having a joint venture with an oil company, frankly speaking. And I think it’s not a good idea to go into business with somebody whose strategies would put you out of business, rather than building the business."

In the end, some experts believe NiMH will serve as an interim solution to more promising lithium systems.

Lithium Ion Batteries
Hitachi is a leader in the development of the lithium ion battery. The battery’s smaller size and lighter weight delivers voltage more than three times that of NiMH batteries while storing large amounts of electricity simultaneously. The batteries also produce higher vehicle power, higher efficiency and provide excellent durability. 

Because it is smaller and lighter, a lithium-ion battery reduces the overall weight of the vehicle to achieve improved fuel economy— 30% better than petroleum powered vehicles. Proponents say that leads to a reduction in CO2 emissions helping to prevent global
Tesla Roadster
warming. Tesla Motors uses this technology which is reportedly the least toxic of the battery types used in automobiles.


What to do with an old battery?
To prepare for a future for electric vehicles — and their batteries, green will not be realized unless there's green recycling as well. Whatever the environmental gains, there's one potential problem, and that is: How to dispose of EV and hybrid batteries once they grow too old and feeble to store and deliver adequate power to move a vehicle?

When will the need will arise?  Although more than 2 million conventional and plug-in hybrids and electric cars are on the road in the U.S., few have been around long enough to dump a profitable flow of batteries to the recycling industry. The Mineta National Transit Research Consortium, however, estimates that 2035 may be the tipping point. There will be somewhere between 1.3 million and 6.7 million worn-out EV hybrid and plug-in vehicle batteries in the U.S.  That's sufficient volume to justify commercial recycling and/or re-use programs, the report says.

Even then, the Mineta report indicates that while recycling to recover individual components
From this...
won't be very profitable by 2035, reusing the batteries — for energy storage at solar or wind-power generating plants, for example, or re-manufacturing them for re-use in vehicles — will only help establish a successful commercial recycling and reuse industry.


Even if the batteries in the very earliest Toyota Prius and
...to this.
Honda Insight hybrids are defunct, those cars were sold in relatively small numbers. Just 19,000 Insights and 33,000 Priuses were sold in the U.S.through the 2003 model year, when the first-generation Prius was retired-- not enough to feed a commercial recycling industry. 


Nevertheless, recycling is an essential part of a battery’s life, even though lithium-ion batteries used in most EVs and plug-in hybrids and the nickel-metal hydride batteries used in most conventional hybrids are not considered toxic. Both types, unlike conventional 12-volt lead-acid car batteries, are deemed safe for landfills. But the world is running out of space for landfill . It would be better for the environment and for the economy if spent batteries are reduced to their components, to be reused instead of being buried in trash heaps.

What Recycling Means for You
Owners of battery operated vehicles, expect recycling to be a painless— maybe even routine— process. Automakers and the auto dismantling industry will handle the recycling. The car owner won't have to do anything except get the vehicle and its defunct battery to a dealer. Recycling is supposed to help keep battery costs down, because it will permit the reuse of the metals and rare-earth compounds that make these batteries work. Re-use is cheaper than mining and processing all-new material in a world depleting its resources. If lithium-ion batteries accounts for as much as half the cost of a new EV, reducing battery costs through recycling will go a long way toward making electric-drive vehicles competitive with conventional cars. A market for used batteries also will help prop up the resale value of electric-drive vehicles— a definite plus for consumers.

Battery recycling helps reduce CO2 emissions and energy use from processing new
Neodymium Sulfate
material. Recycling can also help with energy security. Many of the rare metals used in these batteries come from other countries, and battery recycling will reduce our dependence on foreign suppliers. The primary metals recovered are nickel, copper and iron. The principal rare earths are neodymium and lanthanum. I've never heard of them, but we could start a war over them!


How recyclable are these batteries?
Nickel-metal hydride (NiMH) batteries found in hybrid vehicles are called "zero-landfill" products by the auto industry. They claim that whatever can't be recycled is consumed as fuel in the recycling process, leaving no trash behind. Lithium-ion batteries today are somewhere between 70 and 100 percent recyclable, depending on the particular chemistry of the batteries. Recycling can yield cobalt, copper, iron, nickel, manganese and lithium. Lithium, however, is so cheap there's no incentive for recovering it from lithium-ion batteries today say experts. 

Lithium-ion batteries may enjoy a life of re-use. Even when an EV or hybrid battery can no longer hold and discharge sufficient electricity to power a car's motor, the pack still carries a tremendous jolt. Battery manufacturers claim the packs can still deliver about 80 percent of their capacity when retired from automotive use. The market is lucrative enough that auto companies are partnering with battery, recycling and electronics firms to develop post-automotive markets for lithium-ion battery packs.

For instance, several major power utilities are working with companies— including General Motors, Ford, Toyota and Nissan— to explore the use of these batteries for storage of power produced in off-peak periods by wind turbines and solar generation stations. Lithium-ion packs also are being tested as backup power storage systems for retail centers, restaurants and hospitals, as well as for residential solar systems.

Is a bird in hand worth two in the bush?
by Erika Aoyama


Choosing a green vehicle today almost comes down to an ideological choice. Although we want to preserve the health of the planet and retain as much green in our wallets as possible, we must make judgments about which corporate profit strategy to support.

Battery manufacturers have developed safe, dependable and efficient technologies to move vehicles. Because the vast majority of batteries on the road are still viable, there is no profit to be made in recycling them yet. If and when the tipping point is reached (2035 according to the Mineta Report), battery manufacturers may face other obstacles. 

The next 20 years may see rare earth metal shortages. The automobile industry may elect to concentrate on improved gasoline and diesel engines, either because petroleum remains relatively cheap, or because they do not want to relinquish their aftermarket and auto parts profit centers. And, the oil companies may squelch the battery industry as they have other unwanted competitors.

The bird in hand may be improved gasoline and diesel engines which are progressively leaner and cleaner. Consumer demand will continue to apply pressure through the enactment of laws and buyers’ choice. The future may demand diversity of fuel options in order to preserve our plant’s health and to conserve precious resources, but choosing a green vehicle today can be very confusing.

Since I readily admit my confusion, please check out these additional sources.

Union of Concerned Scientists    http://blog.ucsusa.org/diesel-vs-hybrid-cost-benefits-410

US Department of Energy  http://www.afdc.energy.gov/vehicles/electric_batteries.html

Edmunds.com on battery recycling
http://www.edmunds.com/fuel-economy/what-happens-to-ev-and-hybrid-batteries.html

Plug-in Hybrids: The Cars that Will Recharge America
by Sherry Boschert 

No comments:

Post a Comment