In Stuttgart, Germany, a prototype house is demonstrating what is possible with state-of-the-art renewable energy and building automation technology.

The Aktivhaus B10 is part of a research project exploring how materials, design and technology can extend home sustainability in an increasingly built-up world. The project is being run by E-Lab Projekt, a subsidiary of the Stuttgart Institute of Sustainability that promotes and develops methods and technologies for sustainable building.  Thanks to a smart energy concept and self-learning controls, the building produces double the amount of energy it needs, from sustainable sources. Rather than aiming to stay off the grid, Aktivhaus B10 encourages connectivity — communicating with neighbouring buildings, power utilities, and its fleet of electric vehicles, to fulfil multiple objectives: maximising efficiency, minimising energy costs, benefitting the electricity grid through peak-shifting, and supplying surplus power to the heritage-protected buildings which surround it. With a target of 200% net annual energy production, the Aktivhaus B10 represents a promising new approach to future development and renovation of our built environment. Thorsten Klaus, Head of Building Systems at Aktivhaus, will be speaking the RE•WORK Connected City Summit next month, presenting Activhaus' prototype for future energy connectivity. I caught up with him ahead of the summit to hear more.How did you become involved with the Aktivhaus project? I joined the design team for Aktivhaus B10 while working at alphaEOS on self-learning algorithms for building automation. It was a great opportunity to help develop a real-world testbed for a whole range of cutting-edge technologies, with an ambitious goal: to produce twice as much energy as the house itself would consume, and to use this surplus energy for the transportation needs of its users and the energy needs of its neighbours. The concept of a building sharing its energy was fascinating, and I share the opinion of Werner Sobek, who conceived B10, that this is the most promising approach to the future development of our built environment.  Another primary objective which aligned perfectly with my own design interests was the seamless integration of the technical systems of the house with the architectural concept. As the project progressed this became a major part of my role — acting as an intermediary between the architectural, building physical, and technical design areas.  How have recent technological developments aided the progress of Aktivhaus B10? Compared to its architectural predecessor, "F87” in Berlin (opened in 2011), Aktivhaus B10 features a new generation of technical systems, especially in the areas of building automation and energy management. These systems are intelligent and self-learning, so the house improves its own energy efficiency over time. This was made possible through the development of specialized software at alphaEOS, supported by inexpensive and reliable computing and sensor technology. The sensors for climate control, for example, use the EnOcean wireless protocol to transmit their data as brief telegrams, an efficient approach which allows them to function autonomously, harvesting their energy from a small solar cell on their surface.  While electric vehicles were still relatively rare in 2011 they are gradually becoming more widespread, and B10 was built around the concept of energy sharing between the house and its electric Smart cars and bikes — the house is the occupants' own personal refuelling station. Spurred on by electric vehicle development, battery technology also continues to improve at a rapid rate while decreasing steadily in cost. B10’s stationary battery allows solar energy to be buffered over 24 hours, benefitting the electricity grid by aligning consumption and feed-in to the most opportune times for the overall network. This dynamic energy management is made possible by the increasing connectivity between different devices and systems.  What elements of the connected city do you feel are ripe for disruption? I believe the conventional model we have of energy supply — a centralized power plant supplying energy to individual customers — will be challenged more and more by decentralized energy production and distribution. New buildings which produce a surplus of energy can supply power to their older neighbours, either through net metering arrangements with one another or through third parties which bundle small renewable producers to form more substantial virtual production entities. This transition will likely be complex and challenging, but should ultimately result in a more robust and balanced energy supply.  In addition to sharing energy, a whole range of new systems has emerged in the past few years for sharing modes of transportation — city-wide bike-share programs, app-driven car-share systems, and private vehicles for hire on a person-to-person basis. These innovative models are likely to continue to disrupt the traditional model of vehicle ownership, especially in dense cities, where they are proving to be practical, efficient, and very popular.  What new developments can we expect to see in our cities in the next 5 years? Many national building codes are now requiring new projects to meet net zero energy standards. The next logical step is to push beyond zero energy to net positive buildings — that is, buildings which can produce surplus energy to help meet the needs of the existing building stock (thus reducing the need for costly and resource-intensive renovations). To help manage the complex flows of energy which will arise as more buildings become micro power plants, intelligent building automation and energy management systems will become ubiquitous.  Infrastructure for electric vehicles will likely become a more prominent element of the access concept for new projects, and this will allow innovative new scenarios for urban users — for example, the possibility of charging cars and bikes at the workplace during peak solar production hours and bringing some of this energy home to use during peak demand hours. Bike and car-sharing systems may also be integrated explicitly in many new developments to offer users a wider variety of mobility options.  What do you feel are the most urgent challenges in our cities that we need to address? The most critical issues facing cities on a municipal scale, such as congestion and smog, are typically local symptoms of major global problems, in particular overpopulation and climate change. From changing coastlines to diminished agricultural production, these problems threaten cities around the world as long as we remain dependent on fossil fuel energy. To address these challenges seriously the move towards renewable energy must be relentless. This transition cannot happen fast enough, and one practical and immediately available solution is the integration of energy capture systems — most commonly building integrated photovoltaics — in as many new projects as possible.  As the proportion of locally-produced energy increases, new challenges will be faced — most notably that of energy storage. Questions of how to manage and distribute this energy must also be addressed, and these questions will be as much political and societal as they will be technical.  How can these problems be solved with emerging technologies? The key to unlocking the full potential of renewable energy is large-scale energy storage. This is likely to be one of the greatest technical challenges of our time. There are many promising approaches to storage currently being developed and tested — batteries, flywheels, hydrogen fuel cells, pumped water systems — each with their own advantages and disadvantages. The most effective and realistic solution will likely involved a combination of these technologies, depending on the desired scale and cycling period and the local conditions of the site in question.  As mentioned above, the management of the energy flows resulting from distributed renewable generation combined with buffered storage will require intelligent energy management systems. These systems should aim to be helpful and supportive to users, rather than complex and overwhelming. Machine learning can play a major role in this, relieving the user of many decisions in favour of setting easily understood performance or comfort targets.  What is the role of citizens in creating future cities? Many citizens may of course be working directly on the systems and technologies which shape the cities they live in — architects, engineers, urban planners and many others. But since all citizens will be affected by the direction of development we choose to follow it is most important that they stay informed and active — exercising their right to vote with as much knowledge as possible, and taking part in the discussions which must be held on the issues of energy and infrastructure, and the best ways to respond to the many challenges we face.  Do you feel the smart city stakeholders are addressing citizen engagement effectively? What could be improved? There is most certainly room for improvement in the engagement of citizens with the many issues facing modern cities. Not only in terms of consultation or information about individual projects, but also in the communication of the importance of local projects and strategies to large-scale global problems. An unfortunate trade-off to having access to more and more information is that the depth and quality of this information is often lacking. The speed and superficiality of modern news and social media networks make them poorly suited to communicating long-term perspectives and the complex interconnectedness of many global issues.  It would therefore be highly beneficial for stakeholders to consider the means and the depth with which they communicate and engage with citizens. If a project represents a local contribution to a global problem, or a small-scale example of a system or approach which could potentially be far-reaching, this should be strongly emphasized — a single plus-energy house may have a negligible energy contribution, but thousands, or millions of buildings built according to this philosophy could transform the energy balance of an entire country. Thorsten Klaus will be speaking at the 3rd annual RE•WORK Connected City Summit in London on 16-17 March 2016. Other speakers include Julie Alexander, Siemens; Suzanne Wilson, Bristol is Open; Laurence Kemball-Cook, Pavegen; Kevin Menice, BigBelly and more.Tickets are now limited for this event, for more information and to register please visit the event page here.