Retired engineer designs a 100% self-sufficient off-grid house

Posted on 26 March 2020.

It's official! A self-sufficient off-grid house is no longer a utopian dream! Hans-Olof Nilsson has designed an energy-independent home that performs even in the dead of winter when heating needs in Sweden soar.

The design – known as RE8760 - generates 22,000 kWh of electricity annually.

On Sweden’s west coast near Gothenburg, a special place attracts the attention of circular economy specialists. Welcome to Hans-Olof Nilsson’s home. In 2015, the retired engineer launched a kinda crazy project: to completely do away with the standard electricity grid – a process known as going “off-the-grid” - by designing a 100% self-sufficient house.

In a country where heating needs soar during the long winter and solar panels get very little sunlight, at first sight the challenge would appear to be insurmountable. Yet not enough to dampen Hans-Olof Nilsson's spirits. Against all odds, he developed a large-scale photovoltaic system, possible because the roof of the house he designed has 140 m2 of solar panels fitted. 
  But the retired engineer's real innovation lies elsewhere. To manage both summer peaks in energy production and winter consumption, his self-sufficient house includes an innovative energy storage system. Hans-Olof Nilsson has made use of electrolysis, a technique that converts electrical energy into hydrogen, which can be stored over a long period of time.

 

In the summer, the house converts surplus electricity production into hydrogen, which is then stored in the basement. In the winter, the opposite phenomenon takes over: hydrogen is converted into electricity. The system works thanks to a hydrogen fuel cell designed by a local company. Better still, the hydrogen fuel cell itself produces heat when in operation, which is then used to power the heating system in Hans-Olof Nilsson's house.

In short, the plant operates in a 100% closed cycle: it produces, stores and consumes its own energy and heating. In total, the design – known as RE8760, generates 22,000 kWh of electricity annually.

 

From hobby to business

What started out as a simple undertaking by a keen engineer soon became an industry. In 2017, Hans-Olof Nilsson founded his company, Nilsson Energy, which markets the stand-alone "RE8760" system. And his house has become one of the highlights in the city of Gothenburg with more than 2,400 visitors every year!

While the system looks promising and attracts crowds, it is not without its critics. It is difficult to see any real gain when it costs more than €100,000 to install such a system. By comparison, Swedish households currently spend an average of €550 a year on energy, according to a Swedbank study. It would therefore take 181 years for the investment in the off-grid house to pay for itself! While technical progress is making great strides, this off-grid house still has a long way to go before it is economically viable.

CREDIT: Main picture © Nilsson Energy