The first time you see a Nemoi wind turbine, you may not realize that it is a wind turbine. Nemoi, a silver and white metal structure the size of a garden bush, has three vertical blades that rotate like a carousel around a central axis. Spinning is steady, but completely silent, and doesn’t seem fast enough to generate much power.
According to its creator, the general director of Semtive Energy, Ignacio Juárez, a Nemoi turbine can supply energy to a four-person household at wind speeds of only 16 to 20 kilometers per hour.
Plus, it’s made from 95% recyclable aluminum, can be quickly assembled by one person, and can be manufactured locally.
Smaller, closer, simpler.
We started to wonder why there isn’t a wind turbine on every roof, and we started to think about how to solve the problems of existing turbines.
He explains that conventional turbines require high wind speeds, as well as being large, heavy and difficult to install and maintain.
Large wind turbines cannot be placed in the center of a town or city.
This is why we see wind farms stretching across vast fields in the middle of nowhere. And while those huge horizontal-axis turbines are very efficient, the power they generate has to be transported to end users.
Up to 40% of that energy is lost from its point of generation to its point of use, because it has to be transported, stored and converted. The solution is to produce the energy where you are going to consume it.
And that is what Nemoi turbines do. Once installed and plugged in, they start feeding the network immediately, and can also work without connection to the network. The goal is for each turbine to produce the same amount of energy its owner uses, or more.
It’s the idea of houses becoming smarter, of people generating what they need in their own homes.
Advantages of verticality.
The turbines we are used to seeing have horizontal shafts; like windmills, their blades rotate between parallel and perpendicular to the ground.
These turbines have gotten huge, because bigger means better when it comes to efficiency. Despite the energy lost in transportation and conversion, large turbines are still worth it.
But there is a limit to the size of horizontal axis turbines, and once that is reached, we will need a different solution.
Many experts bet on vertical axis turbines, since they experience a constant gravitational force, always in the same direction. Without the stress of holding 80mm blades at one end, vertical axis turbines can potentially be much larger.
Since their rotation does not take up as much space as horizontal-axis turbines, vertical turbines can be placed closer together in a wind farm, meaning more electricity can be generated on a given area.
If you add more turbines per square foot and less wind to turn them, you get cheaper electricity. With Nemoi, Semtive has taken this concept and made it available for smaller-scale operations.
Juárez and García Enciso are Argentineans and, according to their local mentality, Nemoi’s first big client was the government of Buenos Aires. The city installed solar and wind-powered charging docks at subway stations, public parks and other municipal areas, and put panels and turbines on streetlights.
Since then, Semtive has expanded its customer base to include dealers, utilities, and end users.
End customers use wind energy as a complement to solar energy or as an alternative to installing solar panels.
The turbines have a retail price of $3,600. It’s not a small sum for most homeowners, but government grants and incentive programs are becoming more widespread as states and cities encourage their residents to be more sustainable.
Juarez estimates that Nemoi owners recover their investment in two years, if they have received a discount and live in a high-wind area, or in a maximum of seven years, if there is no discount and they live in low-wind areas. He estimates that the cost of installing solar panels for equivalent power generation is about $20,000.
Given our growing energy needs, the benefits of vertical axis turbine technology, and the cost- and environmental-driven movement for renewable energy, Semtive has a lot of work ahead of them.
Despite five years and countless iterations to achieve the Nemoi design, Juárez and García Enciso are aware that their growth problems are not over yet. Government regulations and energy policies currently pose some significant constraints.
The change in cost-benefit structures that decentralized energy will bring about, made possible by technologies like Semtive’s, will be difficult for utilities, governments and entrepreneurs to navigate. In the end though, it’s hard to go wrong with energy sources that are cheap and green.
Governments are aware that they have to start developing renewable energies. So their policies are beginning to change.
More information: semtive.com