Visiting a sustainability science slam earlier this year I first heard of the so called Own Homes: A house which is built to be completely self-sufficient. The house was meant to get energy solely from the sun and water from the rain. I was intrigued how this can be possible and I have to admit I was quite sceptical about the idea, thinking about it more as an utopia instead of an actual project.
Then, a few months later, I was standing in the wooden construction shell of the first house. And after a very interesting interview with the guys I started to believe that this could be an alternative for the future. The guys are: Klemens, Markus and Robin who founded the project and Malte who joined them roughly one year ago.
Klemens started studying art and gradually occupied himself with biological agriculture, biological architecture and all sorts of research within the area of sustainability. With this project he is realising his dream of a better life in his own self-sufficient home. As a bio-engineer, Robin, is responsible for keeping the house warm bringing in his knowledge of heating and water systems. With his own start-up slowtec is Markus an expert in control and automation technology which makes him responsible for the technique issues within the house. Finally, Malte also works for slowtec and is interested in healthy and sustainable concepts for food which both brought him to the project. This was the talk we had:
How did you start thinking about sustainability?
Markus: I started thinking about it by the start of puberty. At that time, I simply had the feeling that something went terribly wrong. Just over time I began to recognise the different topics and difficulties related to sustainability. During school I was nagging a lot and was generally quite angry with everything. But then I realised that this doesn’t help and decided that I want to try to change things to the better and have fun while doing it. Sustainability is a basic understanding for me.
What would be the most important aspect for you when talking about sustainability?
Markus: Well, that I am not looking at sustainability in a local but in a global way. So for example if I have this super energy saving bike, I also have to ask where the battery is produced. What are the production processes? What are the working conditions? I can do that with every single product. So I always try to think about the whole thing and not just about the local picture.
How did you get the idea of building a self-sufficient house?
Klemens: Actually this question isn’t that different from the former. I think, if you think about how one can live reasonably and if one on top of that, has the aspiration to have fun, then our idea is a good way. Using a minimum of resources and living a good life, leads to the idea of self-sufficiency.
Yes, I read that on your website. You claim that your house offers a holistic concept for living without any sacrifice of comfort. How does that work and what does comfort mean for you?
Klemens: This is indeed a ground-laying question. Comfort means that I get light when I need it and that I get energy when I want it. It also means that I can have a shower when I want to, and preferably a warm one. In the end it is like everywhere in the world: We do have enough resources for everyone, as long as we don’t waste them.
A good example for this is the toilet. If I make hazardous waste out of high quality resources and drinking water it doesn’t proof high intelligence. But this is the process which has been established worldwide. We have the aspiration to make it better.
Can you explain this in more detail? So for example how does your house get energy?
Klemens: Energy is easy; I’ll explain. Water is Robin’s job. Well, energy is more or less constantly available in the form of light from the sun. That’s the reason why we use solar panels on our roof. Solar panels always produce direct current which we use either directly or otherwise store in batteries. The batteries and the whole house are adjusted to direct current. Actually in summer, we have too much energy because we use quite a lot of the roof surface, but that´s so that we will have enough energy even in the darkest days of winter.
Ok, what does that mean? Can I use the stove, wash and charge my laptop at the same time?
Klemens: Theoretically, that wouldn´t be a problem. But it´s absurd. Actually, cooking with electricity is a sin and we decided not to do that. Therefore, there will be no electric stove in our house and instead, we decided to use biological ethanol, which can be produced sustainably.
For the washing machine we thought about something special. It will be used by foot and will be ready after ten minutes (similar to this washing machine). This washing machine will be smaller than normal ones. This shouldn’t be an issue, because the house is quite small and with this one only can acquire a limited amount of clothes which leads to smaller washing loads.
So, I generally think, electricity isn’t a problem. Water is more innovative.
That would have been my next question: How does the water system work?
Robin: We use plants for water purification and through that, we create our own water cycle. So we use our water again and again because we don’t produce any black water. Sewage or black water is normally produced by general toilets. Instead, we use a modern compost toilet, a dry compost toilet in fact. There we compost the excretions and by doing so, we don’t pollute our water with sewage. So we just get grey water from the sink, from the shower with maybe some soap, earth from the gardening and other less severe stuff which the plants can handle and clean completely.
So drugs won’t even get into the water cycle?
Robin: Yes, they go into the toilet…
Klemens: … what drugs?
Well I was thinking about the water cycle and how we struggle with cleaning our water from antibiotics. How can that be achieved by plants?
Robin: Well with just producing grey water. When we talk about compost, there we get so much bacteria, they can even compost drugs. There is more and more research how we can improve and clean contaminated soil or water.
Markus: However, there is no fault in thinking about why this is even a problem. What do I take in? What do I excrete? With the own home I am separated from the water system. I take the rain which should be clean from antibiotics. This means, that we have to think about the issue of responsibility. As long as the water is cleaned and improved out of our sight, then everything seems fine, but as soon as I would start putting my rubbish in my own backyard people would start asking questions.
What happens if it doesn’t rain for around five weeks?
Robin: We have a cistern with 2.000 up to 3.000 litres with which we refill our system regularly. Within the water cycle there are 600 litres.
Klemens: We don’t have that much loss, except the water we drink and what evaporates in our purification system.
How many people are meant to live in your house? Is it a single house or is it possible to live there as a family?
Klemens: Well, how it is built over there, it is a single house, maximum for two people. There is a variation where we have a complete first floor. So in that variation, a small family could easily live. Apart from this, one can also place two houses next to each other.
And who is your target group? Are those people living in the countryside or can I also build the house in the city?
Markus: As long as you have an official authorisation and you like the surroundings, you are completely free to choose where you want to put your Own Home.
What materials do you use to build the house? And how do you ensure that they are sustainable?
Markus: We use wood, clay, limestone, and metal.
Klemes: Well there is relatively little metal.
Markus: We do have screws. The bars have to be screwed together at some points. But out of principle, we can use local wood.
Klemens: Clay comes also from here. It is produced in Balingen. Limestone is sustainable to some extent but not really a local product. These are the main materials. Even with the water tank and in our greenhouse, we use foil and plastic which is produced sustainably. Generally, we just have to see with every material where we can get it.
Malte: Totally, one also has to make compromises. One cannot always make everything compostable when wanting to use it for twenty years.
Markus: The most important aim is to develop a solution which is actually there.
Klemens: And which is doable.
Markus: And which might not be 100 percent perfect – instead of being perfect and not realistically doable. In this way, we make a first step and over time we look for better solutions and make the house even better.
How long does the house last?
Markus: Well the first long term test starts now.
Robin: But we are building our house with wood and normally these kinds of houses last 30 or 40 years.
Klemens: It will last longer than me. And afterwards basically all of the material can be recycled.
As a final question I would like to know how you imagine our life in 25 years?
Markus: I am living together with some friends in a couple of Own Homes. I am working maximum part time. Although I think till then money will be different as well and I think our economy will work differently. There won’t be any classical work. And besides that, I am enjoying nature and the beautifully home-grown vegetables.
Robin: I also like the idea of having a small community of 10 to 12 own homes who are connected to each other. So that there is for example a common laundry room and that it really is a community.
Klemes: If you look down from the airplane these will be the only places with light because the general system will have been collapsed and just within those communities, there will be light and electricity.
Malte: Well, 25 years, that is interesting. This is quite a long time for me. I think there is a trend or better movement that especially young people realise that our society has to change. I mean the Club of Rome claimed it in the 90s already that growth has an end. And this idea is establishing itself as mainstream. I think we will get to the point where people put emphasis on the footsteps we leave behind. People start thinking about how big their influence on the environment is. But also of course how do we organise economy and how do I live with the people around me not just in my direct neighbourhood but also in the neighbouring countries and continents. I at least hope this idea will be enforced.
Markus: There will be a difference between people who have to change their way of living and the ones who will have lived already like this for maybe ten years. Self-sufficiency always has its advantages when the big infrastructures starts to fail. I mean, just think about what will happen if there is a power cut in Stuttgart for 24 or even 48 hours.
Klemens: I mean this is the big misconception: People think they are as independent as ever. But if there is no gas at the gas station, we feel that the contrary is true.