The photos were taken with solar powered camera. Photos: Tiina Junno

The photos were taken with solar powered camera. Photos: Tiina Junno

Global Senses visited an exhibition named “Katolla” (on the roof in English) in Helsinki in early 2017 to find out what kind of creative possibilities the utilisation of large roof surfaces could offer to help in reducing the effects of climate change. The exhibition examined and introduced city roofs according to themes such as architecture, materials, animals, history, atmospheres, living spaces, solar power usage and green roofs. Since Global Senses is exploring creative and intriguing urban solutions that will support the continuity of nature and humanity, the exhibition’s take on solar energy production and green roofs – a roof covered completely or partially by vegetation – was particularly compelling.

We live in a world where we face the effects of climate change every day. If you are someone who wants to make a difference in the world instead of trying to maintain the current unsustainable situation for reasons of money and power, how do you go about it in your own surroundings? In urban and densely built up areas, one way to look for creative and beautiful solutions is to look upwards.

The interest in the utilisation of unused roof areas for solar power production and green roofs is growing every day in Helsinki. Some residential buildings already generate energy with their own rooftop solar power plants, and the city’s plans to create green roofs is well on the way. “Katolla” exhibition showed us that using the so-called fifth dimension of a building for solar energy generation or green roofs can be beneficial for the urban environment.

When an apartment building has its own rooftop solar power plant, it increases energy self-sufficiency and reduces greenhouse gas emissions. Most of today’s energy production and distribution in both fossil fuels and renewable energies is centralised and takes place in large facilities away from consumers. This makes energy self-sufficiency difficult. Furthermore, the burning of fossil fuels in centralised energy production releases carbon dioxide to the atmosphere. From our point of view, one way to support private solar power plants and increase self-sufficiency as well as reduce emissions could be a smart grid.

Smart grids are electrical grids that use technologies and smart appliances, and their way of functioning supports sustainable energy production. We see these grids as potential parts of a creative solution: apartment buildings with rooftop solar power plants could join the grid and share their surplus energy. With the help of flexible technologies, smart grids have a good chance to balance variable renewable energy sources that are challenging due to their fluctuating nature.

For the users of electricity, smart grids offer reliability. The grids can anticipate and act on system disturbances as well as match supply and demand of electricity. This means that one can avoid using energy at peak times and use household appliances or charge laptops when there is a surplus of energy. Not only is it cost-effective for the customer, it can also prevent system overloads on a larger scale when people are not using electricity at the same time. Thus, utilising rooftops for renewable solar energy production fits well with smart grids, makes self-sufficiency of individuals possible and reduces environmental impact of energy production.

Another aspect of the “Katolla” exhibition that caught our attention, was green roofs. Many urban and metropolitan areas – New York being one of the most well-known green roof city to many – around the world are already making their cities more climate-friendly with green roofs. As pointed out by the exhibition, these vegetation covered roofs can help in mitigating climate change. They have a potential to contribute positively to environmental sustainability: they provide insulation that lowers the energy consumption of a building by insulating in the cold, winter months and reducing heat in the warmer summer months.

Green roofs often have several layers, for example, an irrigation layer to water the plants and a drainage layer to steer the excess water out of the roof. Green roofs absorb rain water, create an ecosystem for wildlife, help in lowering air temperatures in urban environment, and reduce the urban heat island – a metropolitan area that is warmer than surrounding rural areas – effect. Furthermore, green roofs can create the much needed natural beauty in urban environments.

Talking with the information advisor of the exhibition revealed that Kalasatama residential and business district, which is still partly in construction, is being built so that it will have green roofs. The entire district will be a smart district with sustainable solutions, e.g. easily accessed public transport, good waste management system and a smart grid. It will be interesting to see what the district looks like when it is completely ready.

It sometimes feels as if the fight against climate change has been taken from the hands of the individuals. Politicians, corporates and climate change naysayers argue amongst themselves while the rest of us watch from the sidelines. But this our world too. And everyone can pitch in. Smart, creative and beautiful solutions, ideas and thinking need to be brought into the consciousness of people to help in protecting our world.

Creative solutions such as utilising rooftops to battle climate change can be a way to change the world for the better. Sustainability in the form of self-sufficient solar energy production and beautiful, environmental friendly green roofs calls our attention to humanity and respect towards nature while we coexist in this world infused with greed, profit and indifference. Resourceful and balanced approach in harnessing the potential of urban roof areas enhances sustainability and helps in lessening the effects of climate change so that we and those who come after us will have a chance. Our beautiful blue globe in space is not owned by anyone. We all belong to it and it belongs to us.


Text by Tiina Junno

“Katolla” exhibition at Laituri, Helsinki City Planning Department’s information and exhibition space, 9 December 2016 to 18 March 2017. The idea, script and implementation of the exhibition by Pekka Hänninen / IAH Arkkitehtuuritoimisto with KSV Laituri (Helsinki City Planning Department). Photos at “Katolla” exhibition by Pekka Hänninen, unless stated otherwise.

Sources: City of Helsinki, Scandinavian Green Roof Association, EESI – Environmental and Energy Study Institute, The New York Times, Green Ribbon