The most common mistake in discussing electric cars is to discuss electric cars. The vehicles themselves are not an in-development, ever-progressing, hopefully-here-someday technology of the far-off future. The technology is very much of the now, and many of the cars are better than their combustion counterparts. Tesla’s “insane mode” takes the Model S from 0-60 MPH in 3.2 seconds. The Mercedes SLS AMG Electric Drive achieves a very literal version of all-wheel drive by dedicating an individual motor to every wheel, with a coordinating computer system determining how much power to distribute to each for maximum performance in every turn and weather situation. Many high-performance EVs are so unremittingly silent that drivers are given the option of activating a road noise simulator.

A similar misstep would be to discuss the viability of off-grid homes in terms of their solar power generation. A 4 KW solar system can generally produce 5,200 kilowatt hours (kWh) per year, or 433.33 kWh per month. This is comparable to many of America’s lower-energy homes; a Maine household uses as little as 531 kilowatt hours per month. While many homes are far beyond these modest numbers — Louisiana residences boast a whopping 1,245 kWh per month — the point is that the technology is already within range of fully servicing many homes.

So, what do these burgeoning business technologies have in common, and why are they the focus of such comparative scrutiny in the public discourse? Batteries. The most dynamic electrical car in the world doesn’t count for much if it can’t hold a charge. Solar panels lose their luster when the sun isn’t shining. And so as certain technologies gather more and more prominence in day-to-day life — environment-conscious vehicles, grid-free households, smartphones, tablets, and so on — the common theme grows in the spotlight, and begins to refocus the conversation. The question of whether or not new tech will catch on is largely moot; these breakthroughs are already here. The question is when their energy storage capabilities will breach the next barrier of not-even-thinking-about-it convenience. With efforts like Tesla’s Gigafactory and upcoming home battery intended to address EVs and solar panels, and Stanford’s fast-charging aluminum-ion battery hoping to help phones and other devices, a whole host of tech may be ready to take a giant step forward.