Prezentace A Way to Cut Fuel Consumption_Hybrid Vehicles_Pohlreich Martin

in other hybrid designs, the motor is used for regenerative braking to recapture energy. The larger motor is used to spin up the engine to operating rpm speeds before injecting any fuel. Many people do not consider these to be hybrids at all, and these vehicles do not achieve the fuel economy of full hybrid models but they are able to get a 10% improvement on the fuel efficiency by shutting down and restarting the engine on demand.
A plug-in hybrid electric vehicle (PHEV) is a full hybrid, able to run in electric-only mode, with larger batteries and the ability to recharge from the electric power grid. Their main benefit is that they can be gasoline-independent for daily commuting, but also have the extended range of a hybrid for long trips. The "well-to-wheel" efficiency and emissions of PHEVs depends on the energy sources of the grid (the US grid is 50% coal; California's grid is primarily natural gas, hydroelectric power, and wind power).

ICE-ICE Hybrid
A basic efficiency problem of the ICE motor is that they must provide enough power for acceleration and this generally requires over 100 horsepower (75 kW). However, the amount of power needed for a typical 3000 pound (1350 kg) vehicle may be less than 5 horsepower (3.7 kW) when running 60 mph (95 km/h) on level roads. So, in an ICE-ICE hybrid a second small motor might be used at cruising speeds. Advantages of ICE-ICE hybrids over Petroleum-Electric hybrids would be greater range and less weight. One of the worst design flaws of the ICE-Electric vehicles is overall vehicle weight in part due to heavy batteries. But, the real waste is that 90% of the time, there is only one person in a 4-8 passenger 3000-5000 pound vehicle.

Fuel-cell
How Fuel Cells Vehicles Work
A fuel cell vehicle is essentially a hybrid vehicle that operates in a way similar to today's hybrids. It is powered by an electric motor, which gets its electricity from a fuel cell stack, instead of an internal combustion. Fuel cell vehicles can use the fuel cell stack alone to power the motor, but most use a second device, either a battery or a capacitor, to assist the fuel cell stack so the vehicle performs well in these more demanding driving situations.

Inside the Fuel Cell

Just like there are different types of internal combustion engines, there are different types of fuel cells. Regardless of the type of fuel cell, all are much more efficient than internal combustion engines. The most efficient internal combustion engine has about 30-percent efficiency. Fuel cells, on the other hand, get between 40- and 70-percent efficiency.
The fuel cell type that looks most promising for automobiles of the future is a Proton Exchange Membrane, or PEM for short.
A PEM fuel cell is comprised of two plates with a catalyst-coated plastic membrane in between. There are channels in the plates, which allow hydrogen and oxygen to pass through on either side of the plastic membrane. The atoms in the hydrogen and oxygen are attracted to each other. But only the proton portion of the hydrogen atom can weasel its way through the membrane to join the oxygen. Because the electron can't make its way through the membrane, it must travel on the outside, and this more circuitous route creates energy. This is the energy that powers the electric motor, which in turn makes the vehicle move. Incidentally, when the hydrogen electron meets up with the hydrogen proton and the oxygen atom, it creates the only by-product of a fuel cell — water.

Making Hydrogen
Despite the fact that hydrogen is the single most plentiful element in the universe, it is most frequently found as one component of another common molecule, such as water, methanol, natural gas or gasoline. As a result, the hydrogen must be extracted from this source through a process that breaks the hydrogen out of its bond with the other element or elements.
One resource being looked at closely is water, because of its wide availability and the fact that it is a "clean" resource. Toyota uses water to produce its pressurized hydrogen through electrolysis