3 ms·

I agree it presents quite a few challenges, and with the tech today it's hard to see solar as viable. However, from what I understand of Mr. Musk's plan, I agre

I agree it presents quite a few challenges, and with the tech today it's hard to see solar as viable. However, from what I understand of Mr. Musk's plan, I agree with his idea that almost all energy on Earth came from the sun (and in the case of hydrocarbons all of it), and so the most efficient way to capture that energy should be directly. Nuclear and geothermal aside, nearly every other form of energy capture we do is indirect and represents a huge waste.

jessriedel 14y ago
The alternate, hand-wavy argument that comes to the opposite conclusion is this: The Earth gets 10^17 Watts from the sun. This power is at it's most diffuse when it initially strikes the Earth as sunlight. After initially striking the Earth, this power transferred into the air, ocean, and land in complicated ways that result in very strong concentrations in some areas (e.g. high winds). Intuitively, it should be easiest and cheapest to go to those places and harvest the energy where it is dense, rather than where it is diffuse. After all, we are not anywhere near tapping into the total energy flux from the sun. It's not a matter of efficiency (sun's ray/usable power) as much as cost. Much better to go and harvest at a place where the energy is 10 times denser than sunlight, even if there were all sorts of losses along the way.
- greghinch 14y ago
  Sustainability has to come into it though. In some mediums this is less of a concern (wind perhaps), but it's paramount when it comes to hydrocarbons. The "cost" right now on sourcing energy from oil and coal does not reflect the true "price" when you take things like pollution into account. This needs to be quantified for all forms of energy collection and extraction in order to have a true representation of value/efficiency. Then solar starts to make a lot more sense.
  - jessriedel 14y ago
    Yes of course. From context, we are restricting our attention to renewables.

jessriedel 14y ago

The alternate, hand-wavy argument that comes to the opposite conclusion is this: The Earth gets 10^17 Watts from the sun. This power is at it's most diffuse when it initially strikes the Earth as sunlight. After initially striking the Earth, this power transferred into the air, ocean, and land in complicated ways that result in very strong concentrations in some areas (e.g. high winds). Intuitively, it should be easiest and cheapest to go to those places and harvest the energy where it is dense, rather than where it is diffuse. After all, we are not anywhere near tapping into the total energy flux from the sun. It's not a matter of efficiency (sun's ray/usable power) as much as cost. Much better to go and harvest at a place where the energy is 10 times denser than sunlight, even if there were all sorts of losses along the way.

greghinch 14y ago
Sustainability has to come into it though. In some mediums this is less of a concern (wind perhaps), but it's paramount when it comes to hydrocarbons. The "cost" right now on sourcing energy from oil and coal does not reflect the true "price" when you take things like pollution into account. This needs to be quantified for all forms of energy collection and extraction in order to have a true representation of value/efficiency. Then solar starts to make a lot more sense.
- jessriedel 14y ago
  Yes of course. From context, we are restricting our attention to renewables.