> It can be done. In the near term, it is conceivable that already-common sources of renewable energy like wind and solar power can meet most of the need. Things would be easier if existing nuclear power technologies were expanded, or at least if we avoided shutting such plants down prematurely.
> But the more fanciful world described above—the one in which, thanks to plentiful energy, the world has eliminated want—is possible only with continued innovation. In the long term, the renewables we currently have will hit a ceiling.
There's a number of people experimenting with converting chest freezers to chest fridges using an external thermostat. Apparently, these can be extremely efficient - people are reporting 10-20% of your 1.1kwH/day number.
Of course, the typical downsides of a chest freezer apply to a chest fridge - they're typically much more limited in size compared to their upright counterparts due to ergonomics, and the larger they are, the more difficult they are to fully utilize.
But they're a lot better than no fridge at all.
Also, a freezer probably has better insulation than a fridge to begin with, since it's designed to hold bigger temperature differential.
My experience with power failures is that the refrigerator will keep the food cold enough overnight if you don't open the door.
Even so, the refrigerator could make ice during the day and be an ice chest at night. No need at all for a battery.
There are numerous heating/cooling applications in which excess capacity at peak capabilities is banked for later use. Thermal energy storage for thermal energy applications is exceedingly efficient as there are no further conversion losses.
Solar power refrigeration which chills an ice block to an arbitrarily low temperature then relies on that to maintain the chilled-compartment temperature during periods of low or no power would be the obvious option.
That’s why the typical middle America “garage fridge” is such an energy hog.
> "There's probably about 3 million households in Rwanda, and a vanishingly small number have a fridge. A refrigerator uses about 2 kilowatt-hours (kWh) of energy per day, so if we were able to get one into every household, that would add about 2 billion kWh (2 terawatt-hours, or tWh) to Rwanda's annual energy usage. That's about as much energy as there is contained in 1 million barrels of oil — and fully one-third of Rwanda's current primary energy consumption."
1) Energy-efficient refrigerators are available at ~1.1 kwH/day. This reduces the needed energy estimate by about half.
2) Energy capture for refrigeration from solar in Rwanda makes much more sense than oil production does. Under full sunlight, a decent 2.5 kW solar array produces about 10 kWH per day (as the full 2.5 KW is only produced at noon, tailing off towards morning and evening). As you probably want to run the refrigerator at night, a battery capable of storing about half that output (5 kWH) would also be needed.
The notion that you'd want to set up an oil-burning power plant (which only converts energy stored in oil to electricity at ~25% efficiency or so) in Rwanda is pretty silly.
As far as claims that there isn't enough land to set up solar panels to provide this minimal home energy supply, the roofs of most dwellings would provide adequate area. It's also possible to grow a wide variety of crops in conjunction with wind turbines and solar panels on agricultural land (wide spacing is all).