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An advantage of the Honda Monkey 125 over science projects is that it is a workable product that is economically viable even in relatively resource constrained

by adolph 3y ago

An advantage of the Honda Monkey 125 over science projects is that it is a workable product that is economically viable even in relatively resource constrained parts of the world. The Monkey 125 has peak power of 7.5 kW and an area of 1.7 m x 0.75 m or 1.3 m^2 [0,1]. The sun delivers a theoretical maximum of 1.3 kW per m^2. In the same area as a Monkey 125 the max solar energy would be 1.7 kW, or 23% of the Monkey 125's peak power (which was probably all used as the team travelled over mountains). Fraunhofer claims a photovoltaic cell with 47% efficiency so a solar Monkey would have about a tenth of the petrol Monkey's ability to move. 0. Specific model used was probably a variant of this Honda, not the OG Monkey that stopped production in 1999: https://en.wikipedia.org/wiki/Honda_Grom https://en.wikipedia.org/wiki/Honda_Grom 1. https://www.hondaprokevin.com/2021-honda-monkey-125-review-specs-motorcycle https://www.hondaprokevin.com/2021-honda-monkey-125-review-s... 2. https://www.pv-magazine.com/2022/05/30/fraunhofer-ise-achieves-47-6-efficient-for-iii-v-four-junction-cpv-cell/ https://www.pv-magazine.com/2022/05/30/fraunhofer-ise-achiev...

ilyt 3y ago
I think the bigger problem is that the rider covers more of the era; if you were able to get even 1.5kW off a small vehicle like that just leaving them outside would likely be enough to recharge enough battery for the journey back (if living close enough). ...but having electric bike/scooter just connected to charger is far more practical way to do it
- adolph 3y ago
  Yes, integrating an energy capture device is not optimal for many/most use cases. A vehicle operating within civilization is better served by having means to receive and store energy. Of energy storage mechanisms, chemical seems more advantageous than kinetic or pressure. From there the question becomes one of ionic or covalent. Covalent has a higher energy density, which is why tanks of hydrocarbons are so ubiquitous.

by adolph 3y ago

ilyt 3y ago

I think the bigger problem is that the rider covers more of the era; if you were able to get even 1.5kW off a small vehicle like that just leaving them outside would likely be enough to recharge enough battery for the journey back (if living close enough). ...but having electric bike/scooter just connected to charger is far more practical way to do it

adolph 3y ago
Yes, integrating an energy capture device is not optimal for many/most use cases. A vehicle operating within civilization is better served by having means to receive and store energy. Of energy storage mechanisms, chemical seems more advantageous than kinetic or pressure. From there the question becomes one of ionic or covalent. Covalent has a higher energy density, which is why tanks of hydrocarbons are so ubiquitous.