1.2 billion people do not have electricity and it costs $800-2000 to connect each of them to the grid. Many countries cannot afford it.
Lithium ion batteries from Tesla and some competitors will reach $100 per KWh by 2018.
Solar power is at about $2 per watt for personal systems in the 10-50 watt range.
People need about 100 KWh of annual solar power which can be produced by about 100 watts of solar for the equivalent of $1000 per capita GDP power.
People need about 1000 KWh of annual solar power which can be produced by about 1000 watts of solar for the equivalent of $5000 per capita GDP power.
Batteries only need to hold 10-15 hours of charge to provide overnight power.
100 watts of solar would need 1 to 1.5 KWh of battery overnight storage.
1000 watts of solar would need 10 to 15 KWh of battery overnight storage.
1.2 billion people would need 12 to 18 TWh of battery overnight storage for the equivalent of $1000 per capita GDP power.
1.2 billion people would need 120 to 180 TWh of battery overnight storage for the equivalent of $5000 per capita GDP power.
As of 2014, the projected capacity of Gigafactory for 2020 was to have been 35 gigawatt-hours per year of cells as well as 50 GWh/yr of battery packs
10 years of production for gigafactory would be 500 GWh/yr.
24 to 36 Gigafactories would be needed for batteries for 1.2 billion people at $1000 per capita GDP power.
240 to 360 Gigafactories would be needed for batteries for 1.2 billion people at $5000 per capita GDP power.
This might be scaled down by 3-4 times if we were only providing the power level to households and not individuals
Similarly small solar power production would need to be scaled up for offgrid electricity to be provided to all people without electricity.
$5 per month ($60 per year) is affordable to most of the global poor, who spend that amount on kerosene and other energy
It will take about 15-20 years to build the battery factories and supply chain to provide enough batteries (beyond batteries for electric cars) to electrify off grid power for developing countries at the $1000 per year equivalent GDP power level and another 10 years beyond that for batteries at the $5000 per year GDP power level. Still by 2050 there should be solar, batteries, LED lighting to achieve $5000 per person per year level for all people. This would be huge as a pathway to eliminate a key aspect of poverty - lack of electrification.
Not just elimination of extreme poverty ($1 per day of 1995 dollars, $1.25 PPP per day at 2005, or PPP $1.90 a day 2011) but getting people up to the what is todays upper middle income level. $10 PPP per day at 1995 dollars.
For the current 2016 fiscal year, low-income economies are defined as those with a GNI per capita, calculated using the World Bank Atlas method, of
$1,045 or less in 2014;
lower-middle-income economies are those with a GNI per capita between $1,046 and $4,125;
upper-middle-income economies are those with a GNI per capita between $4,126 and $12,735;
high-income economies are those with a GNI per capita of $12,736 or more.