Re:The Energy Cost of Electric and Human-Powered Bicycles (2...
by mc32 on Sunday June 30, 2019 @02:38PM
(#20319686)
But that’s an ideal case.
People eat a lot and exercise to lose weight. They don’t eat to only replenish expended energy. They over consume then often compensate with exercise. So a particular rider might eat more or might eat the same regardless of whether they pedaled or they used electric power.
Re:The Energy Cost of Electric and Human-Powered Bicycles (2...
by seanwilson on Sunday June 30, 2019 @04:03PM
(#20320183)
> People eat a lot and exercise to lose weight. They don’t eat to only replenish expended energy. They over consume then often compensate with exercise. So a particular rider might eat more or might eat the same regardless of whether they pedaled or they used electric power.
Some diets aren't as efficient as others though. Feeding corn to cows then eating the cow meat is going to be vastly less efficient than eating the corn directly for example.
Re:The Energy Cost of Electric and Human-Powered Bicycles (2...
by JetSpiegel on Monday July 01, 2019 @12:38PM
(#20327104)
Well, a steak has more energy density than corn. Plus, it has nutrients that simple corn doesn't have.
> The above figures were all produced by assuming average or typical cases. To be fair, it is entirely possible for a bicycle rider to deliberately eat only locally grown and unprocessed foods. In that case, the ratio of primary energy to food calories is closer to 1:1 (Günther 3). Combined with a metabolic efficiency of 25%, this increases the human energy efficiency to 1:4, slightly better than the lithium-ion electric bike.
> ...
> Conclusion: ... Despite the intuitive sense that electric bikes would require more resources than regular bikes, life-cycle analysis shows that they actually consume 2-4 times less primary energy than human riders eating a conventional diet. This conclusion is largely due to the considerable amount of transportation and processing energy that is associated with our western food system.