A 1000 gallon tank stores about 146 gigajoules of energy (diesel motor fuel = 138,700 BTU/gallon, "138700 BTU * 1000 in gigajoules").
1000 gallons of sand (about 6000 kg) heated 1000 °C above ambient stores about 1000 K * 6000 kg * 1.1 kJ/kg-K (from the paper, on page 9) = 6.6 gigajoules.
So to match a fuel tank for energy storage, it needs to be at least 22x the volume, have extremely good insulation (even more volume), a heat-exchanger, and sand-handling augers. Additionally, the sand needed to be heated in the first place, which means a good electrical connection, but if you have that power in the first place, just use that during the winter? The nice part about fuel is that a man and a truck can move a few thousand gallons of hydrocarbons several hundred miles out to the middle of nowhere and transfer that energy at megawatt speed with a hose.
1000 gallons of sand (about 6000 kg) heated 1000 °C above ambient stores about 1000 K * 6000 kg * 1.1 kJ/kg-K (from the paper, on page 9) = 6.6 gigajoules.
So to match a fuel tank for energy storage, it needs to be at least 22x the volume, have extremely good insulation (even more volume), a heat-exchanger, and sand-handling augers. Additionally, the sand needed to be heated in the first place, which means a good electrical connection, but if you have that power in the first place, just use that during the winter? The nice part about fuel is that a man and a truck can move a few thousand gallons of hydrocarbons several hundred miles out to the middle of nowhere and transfer that energy at megawatt speed with a hose.