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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. ...


5

CO2 is produced by burning the carbon in the fuel, so if your driving style causes you to use twice as much fuel, you will produce twice as much CO2. Driving aggressively can have a big impact on fuel consumption. It's hard to quantify, but a 50% increase in fuel consumption and CO2 emissions is certainly possible. Conversely, the CO2 emissions will be ...


3

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 ...


3

There are a ton of different factors to take into consideration here. Lets make sure we keep net GHGe and tailpipe GHGe separate here. Net GHGe Net GHGe: Since 2015, satellite observation as well as international agriculture reporting data have started to show that the original assumptions surrounding Indirect Land Use Change (ILUC) for generation I and ...


3

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:/...


2

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% ...


1

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 ...


1

TL;DR: No -- due to the length of time it takes a coal plant to return to full output after shutting down, it will not produce more emissions during startup than a fully-loaded plant over the same time period. Typical coal plant in the U.S. From the monthly generator inventory I determined that in the U.S. the median utility and independent power producer (...


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