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No. There is no readily available supply of net-positive-energy hydrogen on Earth, where most human power usage takes place. Hydrogen fuel cells may be a useful component of a total energy system but they are not a source of generation capacity. Hydrogen is more like a battery than a supply of energy. Hydrogen can be liberated from water by using energy. ...


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The simple answer is because any feature costs money, so car makers won't include it unless they're forced to. On some models it's available as an option for extra cost - which relies on the purchaser wanting it. On others, where there's no option, it hasn't been designed for that model, so there's design cost as well as per-unit cost to consider. As this ...


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Under RDE [Real Driving Emissions test], a car is driven on public roads and over a wide range of different conditions..... Conditions include: Low and high altitudes Year-round temperatures Additional vehicle payload Up- and down-hill driving Urban roads (low speed) Rural roads (medium speed) Motorways (high speed) Source: https:/...


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So, are fuel cell generators sustainable? Yes. The hydrogen will be generated using spare electricity when wind and/or sunshine are plentiful. It will be stored, and used later to create electricity when there is no wind and sunshine. The key here is that the hydrogen is generated in a sustainable manner: using renewables, not from steam reforming of ...


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The focus on electricity is probably secondary: Any energy source can be converted into electric energy. The focus on fuel cells is probably secondary, too: Hydrogen can simply drive combustion engines as well; if the hydrogen and oxygen sources are sustainable, then the combustion engine will be as sustainable as the fuel cell (minus potential efficiency ...


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There is another possible reason, just a theory mind. Small cars may pass emissions testing without the need for the technology whereas large cars must have it to pass. In other words, it is not necessary for small cars to have the technology to meet emission requirements. (although of course, the vehicles could, with start-stop, still benefit from a 12% ...


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I would say that the OEM engine tune is sufficiently developed to be as lean as possible relative to the fuel octane. And so improve fuel economy by increasing the tire pressure. Also, shorter sidewall tires are possible. For instance a 205/50-15 tire and a 205/45-16 tire have about the same diameter and width but the 205/45-16 tire has a shorter sidewall. ...


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