3 ms·
The energy conversion ratio gives it in calories. About 1.9% for beef. https://ourworldindata.org/meat-production#efficiency-of-meat-production https://ourworl
by indigobunting 3y ago
The energy conversion ratio gives it in calories. About 1.9% for beef.
https://ourworldindata.org/meat-production#efficiency-of-meat-production https://ourworldindata.org/meat-production#efficiency-of-mea...
- Retric 3y agoI'm not seeing 1.9% and that sounds way off. US produces about 27 billion pounds of beef, roughly half of that weight comes from feedlots where they eat ~80% of feedlot calories comes from grains. There's a bunch of numbers tossed around but it's something like 60-70 billion pounds of grain to get those 27 billion pounds of beef.
- bumby 3y agoThis assumes humans could turn 100% of the feed into usable calories. Considering 1) the link defines feed to include grazing and 2) humans are 0% efficient at turning cellulose into calories, the quoted number probably doesn't mean what you think it means.
- Retric 3y agoWe have many ways of turning cellulose into useful calories. Fire being perhaps the oldest.
- deleted 3y ago[deleted]
- bumby 3y agoIf we could eat fire to sustain ourselves, then that would be a cogent point.
- Retric 3y agoEven if you’re just talking about biological calories rather than as a unit of energy, fire reduces energy expenditure to stay warm. Thus acting as a significant food supplement both historically and currently.
- bumby 3y agoThis is still a bit of a stretch to make a relevant point given the context of the discussion. I don’t think many are promoting getting rid of cattle to make room for biomass fuel.
- Retric 3y agoI've seen that argument made several times. EV's are great on land, boats have several options, but for mid to long range air travel biofules have a lot going for them. Unfortunately they need a lot of land. The underlying numbers seem reasonable with US airlines use ~10 billion gallons of fuel per year while the US produces ~15 billion gallons of ethanol being freed up by the rise in EV's. Globally things aren't as rosy, but freeing even 1/5 of the land devoted to grazing, alfalfa, and feed corn would go a long way. Reducing US beef consumption would have positive health impacts. So from a policy standpoint shifting the specific subsides seems like a good idea. Even if we can't get net zero the more we can cut quickly the longer we have to finish the job.
- bumby 2y agoI don’t think that premise holds. With the exception of sugar beets, crops are largely net negative in terms of energy production. You don’t create a more efficient system by adding layers of inefficiency.
- Retric 2y ago> You don’t create a more efficient system by adding layers of inefficiency. We care quite a lot about the form energy takes not just absolute quantities. $4 gets you ~200/kWh from solar enough to drive ~800 miles, or enough premium gas that to send an equivalent car less than 1/10th as far. Similarly, people happily pay 30c/kWh for 300kW fast charging because waiting around is it's own cost. In comparison with bio fuels, green hydrogen is wildly energy negative wasting ~80% of input energy and you need to completely redesign all passenger aircraft.