For years, the game for anyone who owns a battery has come down to one thing: buy power cheap and sell it dear. That logic still holds, but it is no longer the interesting part. What is happening now is that the very largest buyers of electricity are starting to pay for something else. They are paying for credible capacity, meaning the certainty that a given amount of power will be there exactly when the grid and the market need it. A recent deal in the United States shows where this is heading.
What Google actually bought
On 2 June, the flexibility company Voltus announced a three year agreement with Google in PJM, the American grid operator that covers parts of thirteen states and Washington DC. The deal goes under the name Bring Your Own Capacity, and the structure is telling. Voltus will gather up to 100 megawatts of distributed energy resources a year, meaning batteries, smart thermostats and other flexible loads, and tie them together into a virtual power plant that Google finances. The customers who connect their resources are paid by Voltus.
Industry media describe the same thing as a 100 megawatt virtual power plant deal, where capacity from local businesses and households is used to meet Google's capacity needs in PJM. That phrasing is worth pausing on. One of the most cash rich companies in the world is choosing to cover part of its growing power need by paying thousands of small, distributed resources rather than relying solely on building or buying new large scale generation.
Why now
The background is no secret. Data centre load is growing faster than the grid and generation can be built out. When a new facility can be ready in a few years, but reinforcing the power grid takes considerably longer, a gap opens up. In that gap, access to power becomes a strategic question, not just a technical one.
This is where distributed resources come in. Voltus points to an analysis from Brattle estimating that American electricity customers could save more than 100 billion dollars over a decade if existing resources were used more intelligently, including through virtual power plants. The point is that the capacity is already out there in the system. It sits in batteries, heat pumps, chargers and flexible industry. It simply needs to be gathered and made available at the right moment.
What credible capacity really means
The decisive word is credible. Owning a battery is not the same as being able to sell capacity. The difference lies in being able to deliver on demand, every time, and to prove it.
A buyer like Google does not pay for a promise. It pays for a defined amount of power actually being there during the window in which it was pledged, measured and verified. That means a battery needs to be controlled with foresight, kept at the right state of charge ahead of an activation, and reported in a way that holds up to scrutiny. That capability is what turns a stack of hardware into a revenue stream.
Why this matters in the Nordics
It is easy to dismiss an American deal as something distant, but the logic is exactly the same here at home. The Nordic system also faces fast growing load, limited grid capacity and a rising need for flexibility as more weather dependent generation connects. The markets for ancillary services, from FCR to mFRR, rest in practice on the same principle as Google's deal. Whoever can stand ready with power gets paid, whether or not that power is ever used.
What makes the event interesting is not the technology, but who is buying. When one of the world's largest electricity buyers chooses to purchase distributed capacity from small businesses and households, it is a signal about where the value is going. It is shifting from owning megawatts to being able to deliver them the second they are called for.
What it takes to take part
Three things decide whether a battery can actually sell capacity or just sit there looking good.
The first is aggregation. A single resource is too small to be seen on the market. The value appears when many resources are tied together into a whole that acts as one plant.
The second is optimisation. A battery that only does one thing at a time leaves money on the table. The real value appears when power is moved between the spot market, ancillary services and capacity commitments depending on where the payment is best, and when the system automatically prioritises credible delivery over a short term chase of the peaks.
The third is a partner who takes the market role. You need someone to handle the bids, the metering and the balance responsibility, so the owner can focus on the resource being there. That is exactly the full stack we have written about before when it comes to flexibility as a business for commercial properties.
The bottom line
Google's deal with Voltus is small in megawatts but large in what it says. It shows that even the most capital rich buyers see distributed, credible capacity as part of the answer to the power shortage, not as a curiosity. For anyone who owns or is planning a battery, the message is simple. Future revenue lies not only in trading electricity, but in being able to sell the certainty that your power is there exactly when the grid and the market need it.
