The Solution to the Power Grid’s Woes Might Just Be Sitting in Your Driveway

电网困境的解决方案或许就停在你的车道上

You can’t tell when you’re passing one on the highway, but an electric vehicle may well have a superpower. It charges by plugging into the electric grid, of course, but it might also be able to send energy back into it. For a growing number of EVs, this vehicle-to-grid technology, or V2G, creates a revenue stream for drivers, who utilities pay to tap into their batteries when demand on the grid spikes.

当你行驶在高速公路上时，可能无法察觉，但电动汽车其实拥有一种“超能力”。当然，它可以通过接入电网进行充电，但它或许也能将电能回馈给电网。对于越来越多的电动汽车而言，这种“车网互联”（V2G）技术为车主创造了收入来源——当电网需求激增时，公用事业公司会付费调用这些车辆电池中的电能。

Utilities across the country are pursuing pilot projects for the tech, figuring out how to coordinate hundreds, thousands, and eventually millions of EVs. To that end, today a coalition of companies—Eversource, National Grid, EnergyHub, Sunrun, and the Mobility House—is launching an early test of the technology in Massachusetts so utility customers can give it a try. Lessons learned here and elsewhere could drive the technique into the mainstream, making the grid more reliable and electricity cheaper, even if you don’t own an EV. “It’s great to have Massachusetts stepping into the lead here and doing this because these learnings are what’s going to allow this technology to scale,” said Chip Silverman, director of grid services at Sunrun, a solar and battery company.

全国各地的公用事业公司正在推进该技术的试点项目，探索如何协调成百上千，乃至最终数以百万计的电动汽车。为此，由 Eversource、National Grid、EnergyHub、Sunrun 和 Mobility House 组成的企业联盟今日在马萨诸塞州启动了该技术的早期测试，让当地用户能够率先体验。在此地及其他地区获得的经验，有望推动该技术走向主流，从而使电网更可靠、电价更便宜，即便你没有电动汽车也能从中受益。太阳能与电池公司 Sunrun 的电网服务总监 Chip Silverman 表示：“马萨诸塞州能在此领域率先行动非常棒，因为这些经验正是让该技术实现规模化的关键。”

In the new system, participants hook into an existing program called ConnectedSolutions, which allows homes to run off their residential batteries, among other things. Then when there’s a “demand response” event, like during a heat wave, EV batteries can help the grid keep up. Participants are compensated for this, just like some homeowners who provide energy from their solar panels.

在这一新系统中，参与者将接入一个名为“ConnectedSolutions”的现有项目，该项目允许家庭利用家用电池等设备供电。当出现“需求响应”事件（例如热浪期间）时，电动汽车电池可以帮助电网维持供需平衡。参与者会因此获得补偿，就像那些通过太阳能电池板向电网供电的房主一样。

“It’s really kind of a small number of hours per year that you’re discharging the battery,” said Russell Vare, vice president of vehicle-grid integration at the Mobility House North America, a provider of charging基础设施. “It’s not necessarily like a daily discharge. It’s just during those peak times the events are called.”

充电基础设施供应商 Mobility House 北美公司负责车网集成业务的副总裁 Russell Vare 表示：“你每年放电的时间其实非常少。这并不意味着每天都要放电，只有在高峰时段触发需求响应事件时才会用到。”

Utilities like V2G because they’re dealing with escalating, overlapping challenges. For one, the demand for electricity is growing as more power-hungry data centers come online and people switch from internal combustion cars to EVs and from gas furnaces to heat pumps. At the same time, utilities are trying to ditch gas and coal in favor of renewables like wind and solar. These clean technologies, though, are intermittent, in that the wind isn’t always blowing and the sun isn’t always shining. Utilities need ways to bank energy for later use, which is why they’re building storage facilities and even using the Earth itself as a giant battery.

公用事业公司青睐 V2G，是因为它们正面临日益严峻且相互交织的挑战。一方面，随着更多高耗能数据中心的上线，以及人们从燃油车转向电动汽车、从燃气炉转向热泵，电力需求正在不断增长。与此同时，公用事业公司正试图放弃天然气和煤炭，转而采用风能和太阳能等可再生能源。然而，这些清洁能源具有间歇性——风不会一直吹，太阳也不会一直照。公用事业公司需要储存能源以备后用，这就是为什么它们正在建设储能设施，甚至将地球本身当作一个巨大的电池来使用。

Already, Americans are struggling with skyrocketing energy prices for a variety of reasons. Utility shareholders are reaping profits, for instance, and customers are footing the bill for improvements, like burying power lines so they don’t spark wildfires or come down in a storm. Building battery facilities and stringing transmission lines will add still more costs—the inevitable price to pay for a cleaner, more reliable grid.

由于各种原因，美国人已经在为飙升的能源价格而苦恼。例如，公用事业公司的股东在赚取利润，而消费者则在为电网升级买单，比如将电线埋入地下以防止引发山火或在风暴中倒塌。建设电池设施和架设输电线路将增加更多成本——这是为了获得更清洁、更可靠的电网所必须付出的代价。

Except some of that spending may indeed be avoidable: The promise of V2G is that it can make electricity cheaper. While participants need a bidirectional charger to send energy back to the grid, a utility doesn’t need to reinvent the system as a whole. EV batteries are an existing, widespread, and reliable source of backup energy to tap into in times of high demand, like during the summer when everyone is running their air conditioning. “It’s the cheapest cost of flexible energy storage that will be available for the grid,” Vare said.

但其中一些支出或许是可以避免的：V2G 的前景在于它能降低电价。虽然参与者需要双向充电器才能将电能回馈给电网，但公用事业公司无需彻底重构整个系统。电动汽车电池是一种现成、普及且可靠的备用能源，可以在需求高峰期（例如夏季人人都在开空调时）进行调用。Vare 说：“这是电网目前能获得的最廉价的灵活储能方式。”

The hotter the planet gets, the more enticing V2G looks for utilities. People need additional AC to stay healthy, but the appliances require lots of power to run. If that energy isn’t coming from renewables, it’s causing even more warming and increasing demand for AC, and on and on. In a V2G system, vehicles that follow predictable schedules, like school buses and municipal fleets, will be especially useful, in addition to their batteries being enormous stores of energy. Even a typical EV battery, though, has around six times the capacity as a backup unit mounted outside a house.

地球变得越热，V2G 对公用事业公司的吸引力就越大。人们需要更多的空调来保持健康，但这些设备运行需要大量电力。如果这些能源并非来自可再生能源，就会导致进一步变暖，从而增加对空调的需求，形成恶性循环。在 V2G 系统中，遵循可预测时间表的车辆（如校车和市政车队）将特别有用，因为它们的电池本身就是巨大的储能库。即便是一辆普通的电动汽车，其电池容量也大约是安装在房屋外的家用备用电池组的六倍。

While not all EVs have the hardware needed to tap into V2G, more models are, like the Nissan Leaf, coming equipped to do so. And as with any technology, bidirectional chargers will get cheaper over time. “As hardware costs come down, installation becomes simpler, and standards continue to mature, we expect vehicle-to-grid to become dramatically more accessible over the next several years,” said Seth Frader-Thompson, president of EnergyHub, in a statement.

虽然并非所有电动汽车都具备接入 V2G 所需的硬件，但越来越多的车型（如日产聆风）正开始配备此功能。正如任何技术一样，双向充电器的价格会随着时间推移而下降。EnergyHub 总裁 Seth Frader-Thompson 在一份声明中表示：“随着硬件成本下降、安装变得简单以及标准不断成熟，我们预计车网互联技术在未来几年内将变得更加普及。”

With EVs sitting idle all across a city, that adds up to some serious power. So much so, in fact, that only a fraction of owners would need to participate for a program to adequately support the grid. But the more people who opt in, the better, as that gives a utility a broader base to draw from. “If you have a higher number of batteries out there in a virtual power plant, you can actually use less energy from each individual battery,” Silverman said. “But collectively, when you patch them all together and aggregate them, it comes out to a very large resource. And that’s really where the magic is.”

城市中闲置的电动汽车汇聚起来，是一股不可小觑的电力。事实上，只要有一小部分车主参与，就足以支撑电网。但参与的人越多越好，因为这能为公用事业公司提供更广泛的调度基础。Silverman 说：“如果你在虚拟电厂中有更多的电池，实际上可以减少从每块电池中提取的电量。但当把它们整合在一起进行聚合时，就会形成巨大的资源。这正是其神奇之处。”

These early projects are figuring out how best to coordinate this, like with apps that let people specify when they typically use their vehicle to, say, get to work. (Participants in the new Massachusetts program are able to do this.) The overall idea is for EVs to send power back to the grid when demand is highest, like when people return home from work and switch on appliances. Then, as the night goes on, the vehicles can charge. This would be paired with another technique, known as active managed charging, which staggers when EVs juice up through the evening and early morning hours—that is, they’re not all doing so at 10 pm, which would suddenly and dramatically increase demand on the grid.

这些早期项目正在探索最佳的协调方式，例如通过应用程序让人们设定通常使用车辆的时间（比如上班时间）。（马萨诸塞州新项目的参与者已经可以做到这一点。）总体的构想是，在需求最高峰时（例如人们下班回家开启家电时），电动汽车将电能回馈给电网。随后，在深夜时段，车辆再进行充电。这还将配合另一种被称为“主动管理充电”的技术，通过错峰充电，将电动汽车的充电时间分散到整个夜晚和清晨——也就是说，不会出现所有车辆都在晚上 10 点同时充电的情况，从而避免电网需求瞬间剧增。

All told, V2G promises to turn consumers of electricity into more active participants in the grid.

总而言之，V2G 有望将电力消费者转变为电网中更积极的参与者。