Two new customers have arrived on the world’s electricity grids at the same time, and neither of them is a household. One is the data centre running the AI you talked to this morning. The other is the air conditioner that a warming summer has made a necessity rather than a comfort. The grid will answer them with things that take a decade and an argument. A house can answer for itself this month. That is the whole case for a wind turbine on a roof, and it has never been stronger.
Two new customers on the grid.
For thirty years, outside crises, electricity demand in the rich world grew slowly or not at all. That has ended. The International Energy Agency now expects global electricity demand to grow by about 3.6% a year to 2030, roughly half again as fast as the previous decade, and for the first time in a generation it is growing faster than the economy. The agency’s own phrase for it is the age of electricity.
Data centres used about 415 TWh in 2024 and are on course for around 945 TWh by 2030, more than Japan uses today, with AI the main reason. Cooling is the other new customer. Air conditioners and fans already take nearly a fifth of the electricity used in buildings worldwide, and the IEA expects cooling demand to more than triple by 2050 as the number of air conditioners goes from 1.6 billion to 5.6 billion. In hot countries the share of peak demand that is cooling could go from a tenth to nearly half.
Neither of these customers is going away, and both of them arrive at the worst moment: the data centre all day, every day, and the air conditioner on the hottest afternoon of the year, when every other air conditioner on the street is also running.
The supply side takes a decade.
The answers on the supply side are large, slow and contested. A nuclear plant is a ten-to-fifteen-year project and a public argument for every one of those years. A gas plant is faster and dirtier. A new transmission line crosses somebody’s land, and takes years of planning before the first pylon. All of them will be built, some of them should be, and none of them will help a household this winter or next summer. This is not an argument against the grid. It is a timeline.
In the meantime the bill for the new demand lands where it always lands. Prices rise when supply is tight, and the grid is at its tightest exactly when a house needs it most: the heat of a summer afternoon, the dark of a winter evening.
What a house can do in a month.
A household cannot build a power station. It can put a 15 kW continuous-rated motor on a roof or a mast, an Atlas vertical turbine or a Magnum horizontal one, and a set of semi-flexible Flex panels beside it, and start making its own kilowatts before the planning inquiry for the nearest new plant has finished its first hearing. The honest scale matters here: a household turbine does not power a data centre. It powers a house. But a house that powers itself is a house the grid no longer has to, and a million of them is a power station nobody had to build.
We publish what the machine does rather than what we would like it to do. The Atlas reaches 4.5 kW peak with the High-Wind blade set; its curve is 290 W at 8 m/s, 960 W at 12 m/s and 1.85 kW at 15 m/s, quoted at standard air density. The Magnum reaches 12 kW peak. The Flex panel is 460 W. Every figure is on the product page beside a calculator that takes your own wind and sun and tells you what to expect, and when to expect less.
Where the wind is when the heat is.
The two new loads have a shape, and so do the two sources. Cooling peaks on summer afternoons, when the sun is strongest and a panel is at its best. Heating, lighting and the long evenings peak in winter, when the sun is weakest and the wind is strongest. The data centre runs flat, all day and all night, which is exactly the load that neither source alone can cover and that both together, through a battery, can.
| The load | When it peaks | What is producing then |
|---|---|---|
| Air conditioning | Summer afternoons | Solar at full strength |
| Heating, lighting, evenings | Winter, after dark | Wind at its strongest months |
| Always-on electronics | Flat, day and night | Both, through the battery |
| Grid price peaks | Hottest and darkest hours | Whatever you own, not what you buy |
This is why we build both halves. The sun sets every day, everywhere, without exception. The wind keeps different hours. A household system that owns both is awake for the whole day and the whole year, and it is the only kind we recommend to anybody who asks us for independence rather than a discount.
What independence buys.
Three things, in order of how often customers mention them. Price insulation: every kilowatt-hour you make is one you do not buy at the price the grid sets on its worst afternoon. Outage insurance: a battery that a turbine keeps topped up is a house that keeps its lights, its fridge and its router through the evening the substation could not. And the quiet one, which people mention last and mean most: every kilowatt-hour made on the roof is one that was not made by burning something, or by splitting something, on your behalf.
Energy independence used to be an ideology. Three years of price shocks and a warming calendar have turned it into arithmetic, and arithmetic is the only argument we have ever made.
The grid is about to get busier. Your roof does not have to wait for it.
The part most companies leave out.
Measure the site first. If your roof sits deep in a dense old city, walled in on four sides, do not buy a turbine from us; buy the panel. If you are inland with no real wind, put an anemometer up for a month before you put a machine up for twenty years. If you have a strong flat roof, rigid glass may serve you better than semi-flexible, and we will say so. A turbine on the wrong site is a slow way to learn about wind, and we would rather lose the order than teach the lesson.
Independence is worth having only if it is real. The calculator on the product page is there so that yours is.
The grid takes a decade.
A roof takes a month.
Both halves of the day, and the whole of the year.
START WITH YOUR OWN NUMBERS
Atlas vertical wind turbine — 15 kW motor, 4.5 kW peak. Runs the calculator on the product page with your wind.
Magnum horizontal wind turbine — 15 kW motor, 12 kW peak, for open and exposed sites.
Flex semi-flexible solar panel — 460 W, the other half of the day.
The electricity-demand, data-centre and cooling figures are from the International Energy Agency: the Electricity 2026 report (demand growth of about 3.6% a year to 2030), the Energy and AI report of April 2025 (data centres at about 415 TWh in 2024 and around 945 TWh in 2030), and The Future of Cooling and the IEA’s space-cooling analysis (cooling as nearly 20% of building electricity, demand more than tripling by 2050, air conditioners from 1.6 billion to 5.6 billion). The turbine and panel ratings, the power-curve figures and the blade ranges are our own published product-page specifications. The statements about nuclear, gas and transmission timelines are general observations about infrastructure planning, not claims about any specific project. The photographs, including the rooftop at the top of this page, are our own, taken at our own factories, warehouses and installations.