Robatoy wrote:
....

Same, but different, argument about bio fuels. The NET energy is
negative in some cases.

For which cases would you be postulating that, and from what sources?

Only sources I've seen that draw that conclusion rely on assumptions
that neglect portions of the cycle (such as the solar input on the input
side or the usable byproducts on the output) or from very old
sources/processes. These sources have uniformly been funded by groups
whose agenda is to discredit them (like the ads run locally in this area
against a new power plant permit on the basis of air pollution and
carbon sequestration that were actually financed by a large natural gas
producer who is lobbying for new natural gas-fired plants. Talk about a
way to waste a much more valuable resource for other purposes in order
to have a short-term gain! ).

While I'll agree wholeheartedly biofuels aren't going to be the full
answer, they will make a significant conribution, particularly during a
transition period until H or other more exotics are available.

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