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Hybrid vehicles

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Default.png    See also the Hybrid vehicles category.
for subtopics, how-tos, project pages, designs, organization pages and more.


The electric vehicle[edit]

A purely electric vehicle uses a large amount of batteries, combined with a electric motor. They emit no exhaust fumes whatsoever and are thus very useful in certain situations (ie use in enclosed spaces).

Downsides of the electric vehicles[edit]

Amount of battery capacity required[edit]

Purely electric vehicles require a great amount of battery (or rather electric energy) capacity, and thus a huge amount of batteries. At present, lithium ion batteriesW are mostly used (sulpheric acid-lead batteries can be used too, but are generally not used anymore due to their low power/weight ratio). Lithium-ion batteries have a major environmental impact (the production of these batteries atleast, not their use).[verification needed]

Other battery types can also be used (some battery types lowers this impact greatly), but all generally still have a negative environmental effect, and weighten down the vehicle and reduce range (compared to fuel, batteries -regardless of the type- have very low power/weight ratio's.[1]

The hybrid vehicle as a solution to remove a lot of battery capacity[edit]

One solution to reducing the amount of battery capacity is to use a regular series hybrid (to allow using a energy dense fuel rather than electrochemical energy storage) yet swap the battery with a (ultra)capacitor and a range extender (ie microturbine, IC (gasoline) engine, IC (diesel) engine or Stirling engine) fitted to a dynamo or alternator to recharge the (ultra)capacitor.

Swapping the battery with a capacitor eliminates the major downside of the battery (the fact that it is recharged very slowly). This downside hence asked for a large battery, to ensure that the battery wouldn't run dry before the alternator powered by the IC engine had a chance to recharge it. The capacitor can hence be used more as a "buffer" (so storing say energy to drive a few hundred meters upto 1 km, rather than storing energy for say 100 - 500 km).

For the type of IC-engine to be used: although (Beta-)Stirling engines (which are 10% more efficient than IC (gasoline) engines regarding incineration and are very light and allow the use of pure plant oils as fuel) seem useful, they actually aren't really as they can not be stopped and started rapidly (see http://en.wikipedia.org/wiki/Fuel_economy-maximizing_behaviors FAS technique in Hypermiling]). We really need a IC-engine that can be stopped and started quickly, so a regular yet lightweight gasoline engine seems most suitable. Such an engine is ie the quasiturbine.

Advantages of the hybrid electric to purely electric vehicles[edit]

Besides the main advantage of the descreased weight/increased range, and the advantage of eliminating a lot of battery capacity (which is useful as the production of the batteries are environmentally unfriendly), there are additional advantages:

  • Unlike Stirling-only vehicles, Stirling-electric hybrid vehicles can be immediatelly driven after starting. Stirling engines require a "warm-up time", yet due to the capacitor, the vehicle can use the energy still present in the capacitor to immediatelly drive off. The capacitor is then continuously recharged underway. However, due to the inability of the Stirling engine to be stopped/started quickly, the capacitor can not be charged fully (as it would need to be stopped well before the capacitor is fully charged, to allow optimal energy conversion efficiency). This in turn would require a large capacitor, which again adds weight to the vehicle, reducing the efficiency of the system as a whole.
  • Stirling (and Diesel) engines extract more energy and can use other environmentally friendly fuels (ie plant oils) than IC (gasoline) engines.
  • It also still function as a hybrid (allowing to switch to the electric motor within densely populated areas). Electric motors are more efficient here than a heat engine since the heat engine (ie microturbine, IC engine or Stirling engine) would need to operate on a speed/load that is not optimal for it
  • In the specific case of parallell hybrid electric vehicles fitted with a Diesel engine (not a gasoline engine as the latter are more efficient on operating on almost any speed/load ratio):
    • when used on his own (not hybrid setup), the Diesel engine gets into trouble beyond a certain speed/load[2] (it works fine for low speeds/loads though) as it can then not oxygenate its fuel optimally. This results in a lesser energy conversion and thus power loss. The electricity generator (dynamo or alternator) too works more efficient[3] at a specific speed and load. As with series hybrids it's possible to keep the speed/load of both the diesel engine and the electricity generator at a constant rate, near their optimal speed/load range, the efficiency is kept very high during the entire trajectory the vehicle needs to cover.

First Touch of a new Generation

In the 21th century the industry developed more and more vehicle which is able to use green Energy form the socket. The car industry knows that this step is important, because when they miss this step other companies or manufactures came and do this. Furthermore green energy is the further of our world. If you looked at the big company like BMW for example, you can see that they create tow new cars for the customers. In the year 2014 they present the i8 and the i3. This two cars have the best and the highest technology in there.

i8

The BMW i8, first introduced as the BMW Concept Vision Efficient Dynamics, is a plug-in hybrid sports car developed by BMW. The 2015 model year BMW i8 has a 7.1 kWh lithium-ion battery pack that delivers an all-electric range of 37 km under the New European Driving Cycle. Under the United States Environmental Protection Agency cycle, the range in EV mode is 24 km with a small amount of gasoline consumption.

i3

The BMW i3, previously Mega City Vehicle, is a five-door urban electric car developed by the German manufacturer BMW. The i3 is part of BMW's "Project i" and was launched as a new brand, BMW i. The i3 is BMW's first zero emissions mass-produced vehicle due to its electric power train, and BMW is the first company to launch a volume production vehicle on the market featuring carbon-fiber reinforced plastic to improve the vehicle's energy consumption.

Plug-in hybrids[edit]

Plug-in hybridsW are series or parallell hybrids equipped with a power plug. They have the option of recharging the batteries from the electricity grid.

Criticisms[edit]

Costs of private electric vehicles (cars)[edit]

Although the cost of electricity to has been estimated as less than one fourth the cost of gasoline (in California in 2007), the lifetime cost of electric and hybrid-electric cars is much higher than IC-powered cars.[4] This is partly a result of the huge amount of battery capacity installed on these cars, as well as other parameters (ie car weight, non-essential systems, safety precautions, ...).

Another issue is the use of rare earth elements in some electric or hybrid-electric vehicles. especially lanthanum and some 3 other elements seems often used in these vehicles. In some cases, their use can not be avoided, in other cases, they can be avoided.[5][6]

References[edit]

  1. climate scientist Graeme Pearman's comments to Chriswaterguy (after his Lowy Institute talk, 18 Apr 2007) that he had helped to built a hybrid which did not use lithium ion batteries. He confirmed this was the "Eco-Commodore/Holden ECOmmodore
  2. See wikipedia article on "Diesel engine"
  3. This difference can be quite high, ie brushed types can show a difference of 40% !
  4. [http://www.team-fate.net/phev.html "What are Plug-In Hybrids?"
  5. Rare earth elements used in electric and hybrid electric cars
  6. Lithium not being a rare earth element

External links[edit]

See Also[edit]