Hybrid Automobiles have both a gasoline engine and an electric motor. That makes them more complex to repair but more environmentally friendly than traditional forms of automobile transportation.

Plug-In Hybrids and the UC Davis HEV Center

UC Davis' PHEV Center (Plug-In Hybrid & Electric Vehicle Research Center) is working on the next generation of plug-in hybrid electric vehicles (PHEV a.k.a. REEV or EREV) which can be plugged into an electrical wall outlet and charged, for instance, when you sleep at night. A bunch of plug-in vehicles have been built at the HEV Center. Plug-In technology is the ideal solution for both energy crisis and environmental problems, at least for now, while a hydrogen fuel cell vehicle costs about a million dollars. The potential in savings for operating costs is considerable. With gasoline at $3 per gallon (Sept. 2005), the power generated by contemporary hybrid-car engines works out to about 52 cents per kilowatt-hour, while the ability to tap into residential electricity costs only 11 cents per kilowatt-hour.

UC Davis' HEV Center is participating in the ChallengeX competition. In this challenge, sponsored by the US Department of Energy & General Motors, seventeen university teams have been challenged to re-engineer a GM Equinox, a crossover sport utility vehicle, to minimize energy consumption, emissions, and greenhouse gases while maintaining or exceeding the vehicle's utility and performance.

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My husband and I got our our red 2004 Prius last summer. We waited for nearly 6 months. We love her a lot, although our gas mileage isn't as good as we'd hoped. Her name is Harmony. ~JanelleAlvstadMattson

  • That red color is really nice! What's your average gas mileage around town? —JackHaskel
    • The problem for us is that we don't really get to drive in town much. In Davis, I am usually taking small trips and my communte is a straight shot to West Sac. We average between 42-45 overall. One day I got lost in a residential area of Sac and my milage shot up to 54 as I wondered around. Long trips we might get 47 or so. I really just want to have one tank where I get over 50 overall. I have just heard some info about tire pressure, and how that can effect your mileage pretty dramatically. Are you thinking of getting a hybrid? —Janelle

Although not a hybrid, my 98 TDI Jetta (with my username on the plate!) gets around the same mileage as the hybrids coming out. If VW/AUDI come out with a TDI-based Hybrid, the mileage would likely be close to 70 or 80 MPG. For the Record, I currently get 45-50 MPG for highway and 40-45 for city mileage. —TarZxf

  • My friend has a diesel Jetta and loves it. He claims Diesel is better for the environment than regular gas, but I have a hard time believing him. It just doesn't make sense to me, but with that high of mileage, you're still doing your part for the environment and your pocketbook. I wish VW would make a hybrid Beetle. On the subject of license plates, there's a Honda Insight in town with the plate "I (heart) 63 MPG" It always makes me smile. —JanelleAlvstadMattson
    • Diesel has much more energy and releases much more energy per gallon than gasoline, so other than the particulate matter that many diesel engine's release in the exhaust they are much more environmentally friendly. In addition it is possible to make diesel in your garage from waste vegitable oil. —rocksanddirt

Plug-in hybrids make me wonder. Where does the juice coming out of the outlet come from? If it's a nuclear/wind plant, great - but if it's a fossil-fuel plant, what's the point? —DomenicSantangelo

  • Our "juice" inevitably comes from "The Grid," and thus from mixed power sources. But let us imagine that only fossil-fuel power existed: overall emmissions would still be minimized by burning coal or crude oil in large-scale power plants, where efficiencies-of-scale can be realized, and distributing the resulting power to electric vehicles. So rest assured that no matter where they are plugged in, plug-in hybrids will, overall, consume less fossil-fuel than their purely gasoline-powered counterparts. - Erik Anderson
    • This assumes the efficiencies of scale are enough to make up for the power transmission loss between the power plant and the plug (generally ~8%), though this is practically always true. Just something to think about... —Erik Friedlander
      • Duly noted! Similarly, some marginal energy loss is also entailed by transporting fuel by tanker truck and perhaps trips to the gas station on the part of the consumer. But the main consideration is the expense of the refining process itself. Cars don't run on coal or crude oil — in distilling the latter into gasoline, even more energy is expended. - Erik Anderson

I know this little tid bit wont make me popular, but here goes. I would STRONGLY recommended staying away from electric and hybrid vehicles. The hybrid battery is highly unsafe and contains worse gases than that of a large truck from the early 1970's. Also smogs are only done at a max of 45MPH, being that the faster you go in a hybrid, the less electric it is and more gas power it has. At wide open throttle in a prius, it is running richer, which means more CO2 and more NOx. Not to mention the process of making these batteries is horrendous. I know that fact gets tossed around a lot, but its very true. The area where they make these batteries is now so barren that NASA uses it to test their vehicles. Not to mention the numerous safety hazards in hybrids.

As for electric, you are actually doing EXACTLY what gas powered cars are doing. Are you aware that the largest producer of electricity in the US is petro(Fossil Fuels) so you are still in the same circle. If we all used Electric cars, then we would still be using up fossil fuels and still creating green house gases.

Here is a breakdown of electrical sources in the US:

Petro: 40% Coal: 26% Natural Gas: 20% Nuclear Energy: 8% Renewable Energy: 6% :'(

I would also caution against electric cars because they punish those around you. It will cause electric bills for everyone to rise due to supply and demand. Right now those of us on bikes laugh at gas prices. But electric will effect us now. My advice is to go Diesel. It has endless potential, or you can spend money and have your car's air fuel ratio tuned out properly. I did and it was well worth the money. Also, after I had my vehicle tuned it passed emissions with flying colors. So please do some research on what you're buying into, I would hate to see us going in just another circle.

Now before I get a lor of angry messages, I would encourage you to simply look up and research what I said. If I get a scanned I will scan my class books to show you what I know.

Thanks :D —Dozer

  • It's funny, whenever I hear about the relative merits of electric or hydrogen cars, I always think about one of my classes back in my college days, when a professor told us that those methods are basically the same as normal gas, just with a "longer tailpipe". The point is that hydrogen and electric are not energy sources in and of themselves, but methods of energy transmission. Electricity comes from the grid, and the power in the grid is produced in proportion to the sources listed above. Hydrogen generally comes either from fossil fuels/ methane, or from electricity. Thus, what we really need to do is find a better source for electricity, and make a concerted effort to change our infrastructure to utilize those new sources.

Oh, also, non-plug-in hybrids are actually a really good idea, because they increase gas mileage by recapturing energy we normally lose, like the energy from braking. If we can achieve a high efficiency with that, you could get cars that are mostly running on previously generated electricity. Actually, at high enough recapture efficiency, and with good enough solar cells, you could make a car that is not necessarily using gas on normal trips. Just a thought. —JoePomidor

  • This is a Davis Wiki — why are you using statistics for the U.S. at large? More relevant are the California statistics. According to a recent article in the S.F. Chronicle: Just this past Tuesday (April 12, 2011), Governor Jerry Brown signed a law requiring California's utilities to get 33 percent of their electricity from renewable sources by the end of 2020. From the article: "California's large, investor-owned utilities were supposed to meet the original target of 20 percent renewable power by the end of 2010. Two of them came close. Pacific Gas and Electric Co., based in San Francisco, derived 17.7 percent of its electricity from renewable sources last year, while Southern California Edison got 19.4 percent. The new law requires that all the state's utilities, public and private, reach 33 percent in three steps. First, they must satisfy the original 20 percent goal by the end of 2013, at the latest. By Dec. 31, 2016, 25 percent of the electricity they sell must come from renewable sources. Finally, they must hit 33 percent by Dec. 31, 2020."

    You might still not think these percentages are high enough to matter (I would say that they are). But at least consider the relevant facts. —CovertProfessor