&gt; Since, due to physics, electricity is very hard to store and there are already transmission lines,<p>You&#x27;re going to have to actually argue &quot;due to physics&quot; on this one, it&#x27;s far more like &quot;due to technology and engineering.<p>Transmission lines are hugely expensive, involve stringing valuable materials for miles. The cost is going to vary widely throughout the grid, but the EIA estimates an average of ~$0.04&#x2F;kWh across the entire US [1].<p>Most storage costs are somewhat easier to estimate, as batteries costs are well known. Current prices on new lithium ion batteries put the cost at ~$0.15-$0.20&#x2F;kWh. This is probably not the most cost effective storage model, vanadium redox flow batteries, or hydro storage, or used car lithium ion batteries will drive this down substantially. Also, storage costs are dropping dramatically, while transmission costs are unlikely to change much.<p>For many locations, it may make far more sense to pay $0.20&#x2F;kWh than to build out the grid to that location.  And this is definitely true for many locations, even in California, that are only a few miles away from grid-connected homes. It&#x27;s all a matter of the costs of current technology, discount rates for the cost of up-front capital investments, and the expected tech curve.<p>Long-distance transmission does have the potential to hugely improve the cost-effectiveness of intermittent renewables. A recent study tried to optimize costs using high-voltage DC interties between US grids to distribute renewable energy across the country, and found that storage was not necessary, even when transitioning a huge percentage of the power source to renewables. [2]<p>&gt;There are going to be factories that probably can&#x27;t realistically be supported by batteries<p>This again is all a matter of cost.  I do think that transmission can help a ton here. But I think there&#x27;s going to be both time shifting (storage) and distance shifting  (transmission) in the future.<p>I think that people underestimate the rate at which storage will get cheap, just as they did with wind and solar, but that&#x27;s just my humble opinion.<p>[1] <a href="http:&#x2F;&#x2F;www.eia.gov&#x2F;forecasts&#x2F;aeo&#x2F;pdf&#x2F;tbla8.pdf" rel="nofollow">http:&#x2F;&#x2F;www.eia.gov&#x2F;forecasts&#x2F;aeo&#x2F;pdf&#x2F;tbla8.pdf</a><p>[2] <a href="http:&#x2F;&#x2F;arstechnica.com&#x2F;science&#x2F;2016&#x2F;01&#x2F;making-a-single-us-electrical-system-boosts-renewables-lowers-costs&#x2F;" rel="nofollow">http:&#x2F;&#x2F;arstechnica.com&#x2F;science&#x2F;2016&#x2F;01&#x2F;making-a-single-us-el...</a>