Charge at Night, Save Money, Cut Emissions

Every evening, electricity demand spikes. People get home, turn on the stove, crank the heat or AC, and switch on the lights — all at once. In places where electricity comes mainly from coal or gas, that means firing up extra power plants to keep up, which pumps more pollution into the air. In some cities, EV adoption is already high enough that the evening charging rush is a real and growing strain on the grid — making the timing of when you charge more important than ever.

The NASA video below shows CO2 drifting through Earth’s atmosphere, carried by wind. It’s detailed enough to track emissions from individual power plants and watch them spread across the globe. You can even see CO2 levels rise and fall with the rhythm of daily human activity — proof that the day/night cycle of pollution is real and visible from space. A reminder that your choice of when to use power can have a real impact.

Now think about overnight. Most people are asleep, not driving, and definitely not plugging in. Electricity demand drops, so the grid has plenty of spare capacity. In places that rely on coal or gas, that also means fewer power plants running — so the electricity is cleaner. It’s often cheaper too, if your utility offers time-of-use pricing, where the rate you pay changes based on when you use electricity. Not every utility offers this, but where it’s available, overnight hours are typically the cheapest on the clock. For most EV drivers, a full night of charging from a regular wall outlet adds enough range to cover the next day’s commute.

It also helps to understand the difference between the two main types of home charging. A Level 2 charger pulls around 7 kilowatts and can fully charge most EVs in 3 to 5 hours — it’s fast and convenient, and there’s nothing wrong with it. But because it draws so much power in a short window, timing matters: a Level 2 session starting at 6pm hits the grid hard right when everyone else is also using electricity. Used overnight, that same Level 2 charger is great — it finishes quickly during off-peak hours, when the grid has plenty of spare capacity to absorb it. A standard 120V Level 1 outlet, on the other hand, draws about 1.4 kilowatts — roughly five times less. It charges slowly, trickling power into the battery over 8 to 12 hours. That slow, steady draw is naturally spread across the night, so even if someone plugs in right after dinner, most of the charging happens while they sleep, when the grid is quiet. For most drivers’ daily needs, it’s enough. That said, if dozens of residents all plug in at once, even small loads add up — which is exactly why pricing tools matter for L1 as well as L2.

The problem for people in apartments and condos is that they often can’t charge at home at all — let alone choose when to do it. That’s exactly the gap EVnSteven is designed to fill.

With EVnSteven, building managers can set the price of charging based on the time of day. Generally speaking, the evening rush runs from about 6pm to 11pm, and overnight from 11pm to 7am — and managers can set a different hourly rate for each window. To give a rough idea: a building might charge $0.50 per hour overnight and $2.00 per hour during the evening rush — the exact rates are up to the manager, but the gap creates a real incentive for residents to wait until bedtime. The app tracks usage by the hour and bills residents monthly, who then reimburse the building. Buildings can set their rates to simply recover their electricity costs, or price higher to generate a profit from the service. That’s entirely up to them. If a resident forgets to charge overnight and needs a top-up before work, they can still plug in — they just pay the higher peak rate. The choice is always theirs.

Getting started is straightforward. EVnSteven works with standard 120V outlets, so many buildings can begin using outlets that are already there. Where new outlets are needed, they’re significantly cheaper to install than Level 2 chargers — L1 runs on thinner copper wire, which costs less to purchase and run through a building. The app handles billing automatically, so once rates are set, there’s nothing for the building manager to monitor or manage day to day.

For buildings that have both Level 1 and Level 2 outlets — or are considering adding Level 2 alongside an existing Level 1 setup — EVnSteven offers the best of both worlds, with independent rate-setting for each charger type. Level 2 stalls can be priced lower overnight — rewarding residents who wait — and higher in the evening, to encourage them not to grab a fast charge right at peak demand. Level 1 outlets can have gentler pricing throughout the evening and overnight, since their small load is easy on the grid regardless. The result is a flexible system that works for different residents and different schedules.

When it works as intended, the benefits stack up. Residents who charge overnight pay less and rarely have to think about it. Building managers who price thoughtfully recover their electricity costs without any big upfront investment. And in places that run on fossil fuels, shifting even a portion of charging to off-peak hours means fewer extra power plants spinning up — and less pollution overall. The key is that nobody has to be an environmentalist to make it work — they just have to prefer paying less. That’s a pretty reliable motivator.