Energy Storage (Distributed)
A battery in the garage, in the basement, in the car. Millions of them, coordinated, become a power station that nobody had to build.
The effect compounds within years. Put it in place and it keeps working.
Origins
For a century, storing electricity at home was a thing only eccentrics and off-grid idealists did, with a shed full of lead-acid batteries, a hydrometer, and a great deal of patience.
The batteries were heavy, toxic, short-lived and unforgiving. You had to top them up with distilled water. Discharge them too far and they were ruined. It was a hobby, and it was a hobby for people prepared to become amateur electrochemists.
What changed was not a breakthrough in grid technology. It was a camcorder, and then a laptop, and then a phone, and then a car.
Lithium-ion was commercialised by Sony in 1991 for consumer electronics. It scaled because billions of people wanted portable devices, and then it scaled enormously because Tesla and others decided to put thousands of those cells into a car. Every doubling of production drove the cost down, and the cost fell about 89% between 2010 and 2023, and at some point along that curve a home battery stopped being an indulgence and became an investment.
The grid is being reshaped by a technology that was perfected so that people could film their children’s birthday parties. This is a recurring theme in the history of energy and it should make us humble about forecasting.
What it actually is
Distributed storage means batteries at the edge of the grid rather than at the centre: in homes, in businesses, in electric vehicles.
It does three things, and the third one is the interesting one.
It makes rooftop solar work properly. Without storage, a household exports power at midday when it is worth least and buys it back at 7pm when it is worth most. A battery closes that gap and roughly transforms the economics.
It provides resilience. When the grid goes down — and as weather worsens, it will go down more — a house with a battery keeps its lights, its fridge and its medical equipment running. For a growing number of people this is the actual reason they buy one, and the climate benefit is incidental.
And, aggregated, it becomes a power station. This is the part almost nobody has internalised. Ten thousand home batteries, coordinated by software and dispatched together, behave as a single large power plant — a virtual power plant — that can respond in milliseconds, is distributed across the whole network, has no single point of failure, and was paid for by its owners.
The utility does not have to build it. The customers already did.
And the largest version of this is not in basements at all. It is on driveways. A private car is parked roughly 95% of the time, and an electric car contains a battery many times larger than a typical home unit. A national EV fleet is, in aggregate, the largest distributed battery ever assembled, and it is currently doing nothing.
The numbers
The cost collapse. Battery costs fell approximately 89% between 2010 and 2023, driven overwhelmingly by electric vehicles rather than by grid demand.
The idle fleet. Cars are parked around 95% of the time. An electric vehicle battery is typically several times the size of a home storage unit. The distributed storage resource sitting on driveways dwarfs anything utilities are planning to build.
The economics of rooftop solar. A battery roughly transforms the value of a domestic solar system, by letting the household consume its own generation in the evening rather than exporting it at the moment it is worth least.
Virtual power plants. Aggregated home batteries can respond to a grid signal in milliseconds — faster than any thermal plant — and are distributed across the network rather than concentrated at one node. In several markets, householders are now paid for this.
The honest limits. Distributed storage is more expensive per kilowatt-hour than utility-scale storage, because installing one battery at a time in a garage does not benefit from industrial scale. And, like rooftop solar, it is bought by people with capital and roofs, which raises the same equity question.
Why it matters
There is a battery in the garage, and it is quietly doing something that used to require a power station.
It stores the afternoon so that it can be used in the evening. It keeps the fridge running when the storm takes the line down. And, if it is connected to the right software, it stands ready to support a grid serving a million people, along with ten thousand others just like it, and it responds faster than any turbine ever built.
Nobody had to construct that power station. Nobody had to find a site for it, or fight a planning battle, or run a transmission line to it. It was assembled, one garage at a time, by people who mostly bought it for their own reasons — to save money, to keep the lights on, to feel a little less dependent.
That is a genuinely new kind of infrastructure and we do not yet have the language for it. It is not public and it is not private. It is not centralised and it is not isolated. It is a common resource, made of privately owned pieces, and it works better the more people join.
Which is, when you think about it, what a community has always been.
What it actually takes
Market rules that let it participate. A home battery can provide frequency response faster than a gas turbine. In most markets it is not allowed to be paid for doing so, because the rules were written when only large generators existed. This is the entire bottleneck and it is regulatory, not technical.
Vehicle-to-grid, which is technically ready and commercially stuck. Bidirectional charging works. The obstacles are standards, warranty concerns about battery degradation, and the fact that no one has quite worked out how to pay people fairly for it. The prize is very large and the progress has been slow.
The equity problem, again. Batteries are bought by people who own homes and have capital, and the grid services they provide are paid for by everybody. Without deliberate design, this becomes another mechanism for transferring value to the already comfortable.
Aggregation, which requires trust. Virtual power plants only work if householders let somebody else dispatch their battery. That requires a genuinely good deal and genuinely clear terms, and the sector has not always offered either.
Recycling, before the wave. Millions of home and vehicle batteries will retire in the 2030s and 2040s. Building the recycling capacity now is far cheaper than discovering the problem then.
Where it matters most
Australia has the world’s highest rooftop solar penetration and is furthest along in aggregating home batteries into virtual power plants. It is where the rest of the world will learn how this works.
California and the American Southwest have the sharpest duck curve and increasingly frequent grid shutdowns for wildfire risk, which has turned home storage from an environmental purchase into a practical one.
Germany has a very large installed base of home batteries paired with rooftop solar, and one of the most developed markets for aggregation.
Puerto Rico and the Caribbean are where resilience is not a preference. After Hurricane Maria, home batteries stopped being a luxury and became a way of not losing your insulin.
Off-grid East Africa and South Asia, where a small battery beside a solar panel is not a grid service at all. It is simply the difference between having light after sunset and not.
How to tell it’s being done well
Can it be paid for what it does? A home battery can respond faster than a power station. If the market will not pay it for that, the value is being thrown away.
Is the aggregation deal fair? Virtual power plants require householders to let someone else dispatch their battery. That needs clear terms and a genuinely good deal, and it has not always been offered.
Who can afford it? Batteries are bought by people with capital and homes, and the services they provide are paid for by everyone. Without deliberate design this transfers value upward.
Is there a recycling plan? These batteries retire in fifteen years and the date is already known.
What you can do
Anyone
- A home battery roughly transforms the economics of rooftop solar, because it lets you use your own power in the evening rather than exporting it at midday for very little.
- Your electric car is a battery that is parked 95% of the time. In a growing number of markets you can now be paid for letting the grid use it.
Homeowners
- Resilience is increasingly the real reason people buy: keeping the fridge, the lights and the medical equipment running when the storm takes the line down.
- Ask whether your battery can join a virtual power plant. In several markets you will be paid for it.
Policymakers
- Change the market rules. A home battery can provide frequency response faster than a gas turbine and in most markets is not permitted to be paid for it.
- Make vehicle-to-grid work. The technology is ready; the standards, warranties and payment mechanisms are not, and the prize is the largest distributed battery ever assembled.
- Design for equity. Batteries are bought by people with capital, and the grid services they provide are paid for by everybody.
Business and investors
- Virtual power plants are a genuinely new asset class built from hardware that customers have already paid for.
- Battery recycling capacity must exist before the retirement wave of the 2030s, and it barely does. The feedstock is already installed and the date is known.
Who is working on this
We are researching which organizations in our directory of 8,493 actively work on this solution, and we only list an organization once we have verified it. That research is ongoing. In the meantime, search the directory yourself:
Questions
What is distributed energy storage?
Batteries at the edge of the grid rather than at the centre: in homes, businesses and electric vehicles. Individually they store a household's solar power for the evening and keep the lights on in an outage. Aggregated and coordinated, thousands of them behave as a single power plant.
What is a virtual power plant?
Thousands of home batteries, coordinated by software and dispatched together, behaving as one large generator. It responds in milliseconds, faster than any thermal plant, it is distributed across the network with no single point of failure, and critically it was paid for by its owners rather than by the utility.
Can my electric car really support the grid?
In principle yes, and it is the largest untapped storage resource anywhere. Cars are parked roughly 95% of the time and an EV battery is several times larger than a typical home unit. Bidirectional charging works technically. The obstacles are standards, warranty concerns about degradation, and nobody having settled how to pay people fairly.
Why did batteries get so cheap?
Consumer electronics and then electric vehicles. Lithium-ion was commercialised for camcorders in 1991 and scaled through phones and laptops and then cars. Costs fell about 89% between 2010 and 2023, driven by demand that had nothing to do with the electricity grid. The grid is being reshaped by a technology perfected so people could film birthday parties.
Is home storage cheaper than grid-scale storage?
No. Installing one battery at a time in a garage does not benefit from industrial scale, so it costs more per kilowatt-hour than a utility-scale installation. What it offers instead is resilience, self-consumption of your own solar, and no need for new transmission.
Is it fair?
Not automatically, and this deserves to be said. Batteries are bought by people who own homes and have capital, while the grid services they provide are paid for by everybody. Without deliberate design, distributed storage becomes another mechanism for transferring value to people who are already comfortable.
Sources
- Project Drawdown - Deploy Distributed Energy Storage (Drawdown Explorer) Framework and classification. Cited, not reproduced.
- IRENA (2025) - Renewable Power Generation Costs in 2024
- IEA - Grid-Scale Storage and demand response
- Rocky Mountain Institute - virtual power plants
- IPCC (2022), AR6 Working Group III - Energy Systems
The solution taxonomy follows the framework popularised by Project Drawdown. The analysis above is our own; for their carbon modeling and rankings, visit them directly.