Talk:Environmental Impact
Does it make sense to add discussion of food and/or recharge facilities to Environmental Impact? If the laptop battery is recharged using muscle power, it will also impact the food a child needs. A simple conversion assuming a 90% efficient charging cycle and 15% efficient human food to muscle power conversion results in 105-140 calories of food required for each laptop recharge. Extra calories used due to thinking more aren't included! --MWarren 20:15, 5 December 2007 (EST)
| NiMH | LiFePO4 | |
|---|---|---|
| Wh | 16.5 | 22.0 |
| cal | 14187.4 | 18916.6 |
| kcal (aka food Calories) | 14.2 | 18.9 |
| charge cycle efficiency 90% | 15.8 | 21.0 |
| human food to muscle work conversion efficiency 15% | 105.1 | 140.1 |
- One of the reasons why the solar option is so appealing. --Walter 21:11, 5 December 2007 (EST)
- Also, even in the 3rd world, a majority of children have some play room between the calories they consume and the physical work they are expected to do. If they don't, a laptop is really not what they need anyway, and probably not what anybody would give them, to boot. Homunq 22:01, 5 December 2007 (EST)
- Hopefully the children do have some extra play room; the issue of food and/or recharge facilities seemed like another good topic for this page. Here is how Dr. Negroponte responded to the laptop vs. food question in an OLPC Analyst Meeting:
- "...Why give laptops to kids who are dying of hunger, malaria, who don't have clean water?"
- The answer to that question is very simple, just substitute the word "education" for "laptop" and you'll never say it again. Because, clearly, if a child is dying of hunger that child needs food right then and there. Education is not on .. it's a separate thing.
- But when you solve and you address and you work on all of those problems nobody I know would say: "By the way, let's hold off on education." The reason you don't do that is because education happens to be a solution to all of those same problems." --Nicholas Negroponte
- --Mwarren 13:28, 6 December 2007 (EST)
Power Consumption
This information appears to be misleading but could easily be cleared up:
"Assuming 2000 hour use per computer per year at the low end of power consumption (idle-mode), and an average 3 year lifetime, 87 billion kilo-watt hours are used to power the world’s personal computers per year. If every personal computer was replaced by an OLPC XO laptop, just 1.5 billion kilo-watt hours would be needed: thus 85 Billion kilo-watt hours could be saved."
I tried to sort out the calculation and came up with a power consumption of 3.3 watts. A previous calculation using a 16.5 watt-hour battery capacity divided by the 3 hour operating duration cames up with 5.5 watts of power required... Something seems off but it could possibly be a blending of operating versus idling power requirements. The statement above could be cleared up by listing the OLPC "operating" power consumption.