About Zero Sun™

Zero Sun is one of Sweden’s most exciting energy projects right. In the southern entry into Swedish Lapland, in Skellefteå, we are building a house that will be completely self-supporting with solar energy – in a place where the sun does not show its face for much of the year.

The project is an experiment to make solar technology more accessible, thereby becoming a piece in the puzzle to switch society over to 100 per cent renewable energy. In accordance with the EU climate objectives.

If we can make it here, we can make it anywhere

Building a house that relies fully on solar power is one thing. Doing it in a place where sunlight is rare is something else entirely.

And then to do it off grid, i.e. separate from the regular electrical grid where we as an energy company have historically seen most of our business, is a challenge.

But we are also looking for a challenge in this project. By challenging ourselves with new innovative solutions, we can learn important lessons about the energy provision of the future. Another way of putting it would be “If we can make it here, we can make it everywhere”.

Once the Zero Sun house is completed, it will be completely self-supporting in terms of energy – all year round. In this context, energy refers to the electricity and heating consumed in the house, but also to having sufficient electricity and hydrogen to regularly fill up the household’s vehicles.

The dark and the cold is part of everyday life

For those of us who live and work close in Skellefteå, the dark and the cold is part of everyday life for much of the year. But it tests the energy provision to our homes.

Building a house that runs completely on its own solar power is one thing. Doing it in a place where sunlight is rare is something else entirely. The solar energy that is generated during the summer months has to last throughout the year, which is a challenge.

The idea is that anyone should be able to rent the house to see what it is like to live in a house that is not connected to the electricity grid. By making it possible for more people to try this new technology and the energy provision of the future, we hope that many will share in the experience of living in a unique energy house. Without being cold or lacking hot water.

Modern one-storey house

Zero Sun is a modern one-storey house from the standard range of the Swedish company A-hus. The only customisation of the house is a small upgrade of the window energy class and that there is an equipment room.

On the outside, the only thing that could possibly indicate that this house is self-supporting would be the 122 m2 of solar panels on the roof.

This is how the solar energy in Zero Sun works in a place with limited sunlight

Solar panels on the roof collect solar energy, which is primarily used for the direct energy consumption of the house. Any leftover energy is then stored in batteries. Once the batteries are full, the surplus energy goes into producing hydrogen by way of an electrolyser, which is stored in a separate tank.

During the darkest time of the year, in the winter, the stored hydrogen is used to produce electricity via a fuel cell. That way, the house gets its energy from the sun – all year round.  In addition, the fuel cell is cooled by water, which is an important function when connecting fuel cells to a house.

The reason for this is that, when operational, it generates hot water, which is brought back into the house to be used for heating and hot water. All of this comes packaged in an equipment box installed in the garage, a solar roof and storage of seasonal energy in the form of hydrogen on the property.

In addition, the house can fuel cars on the property as needed. If you have an electric car, you charge it with electricity, and if you drive a fuel-cell vehicle, you fill up with hydrogen, of course.

The Zero Sun house can influence behaviours

The energy challenges of the future are not only about producing energy in a smarter way, but also about smarter energy use.

In one way or another, guests at the Zero Sun will be able to monitor their energy consumption, look at the energy balance and get a prognosis of how long the energy will last.

Based on the energy balance, the Zero Sun can tell you what the energy has been used for, what the visitors have been doing at a certain time, for example, how long they have showered or how many loads of laundry they have done, as well as how this has affected the energy balance of the house.

This in turn gives an opportunity to communicate when there is surplus energy. This involves, for example, recommending the tenants to charge the electric car or run the dishwasher.

So far, smart houses have been more about comfort and surveillance. Due to the possibility of guiding behaviours, we are now going one step further by also influencing how and what the visitor does to optimise their energy use.