Green Solution House

German Sustainable Building Council (DGNB) Certification

At Green Solution House we explore circular sustainability. The exploration is rooted in three sustainability strategies and constantly informed by local conditions and pragmatic use of resources. Green Solution House is certified to the standards of the German Sustainable Building Council (DGNB). The design is based on the criteria of the Active House vision and inspired by the Cradle to Cradle life cycle concept. We wanted the best building possible for the times, one that would contribute to the health of both people and nature. We developed criteria for material selection, in order to exclude harmful substances; materials should be healthy for those using them and carefully sourced – locally if possible. Sometimes our exploration led us to pragmatic, low-key solutions. ”If it ain’t broke, don’t fix it” became our guideline for renovating and everything possible was reused or recycled back into the project. Building upgrades were made with the aim of increasing performance and comfort. The new building is designed to be an envelope enclosing great meeting and learning spaces with outstanding indoor climate and daylight quality.

Holistic Approach to Sustainability
The design of the building itself is based on several parameters to show a holistic approach to sustainability. The building is certified to the standards of the recognised German Sustainable Building Council (DGNB), based on the criteria of the Active House vision and inspired by the Cradle to Cradle life cycle concept. The building and landscape present the latest developments in the field of sustainable architecture; we show that sustainability involves more than aspiring to green certification, and that it is possible to quantify our project’s high quality on the basis of several parameters.

Utilising the Existing
‘If it ain't broke, don’t fix it’. At the Green Solution House we believe in the value of re-purposing and eliminating waste. This thinking has been applied to many aspects of the refurbishment and expansion of the buildings, as well as the landscape design. Parking space is built on a base of rubble from the demolished buildings that used to occupy the site. The remaining buildings received a facelift with new energy efficient façades and roofing, although most of the original features remain. Like the buildings, the furniture, light fixtures and much much more were given a facelift and re-integrated in the hotel’s interior. Some furniture was reupholstered with Cradle to Cradle certified textiles. What could be used was reclaimed and re-purposed, what couldn't was donated to charity. Our approach is to be responsible, for us this is both better for the environment and the finances.

Resourceful Thinking
Bornholm is a very resourceful island and we benefit from that at Green Solution House. Instead of having to transport materials and services from far we use local everywhere possible. Raw materials like granite and wood are used in the landscape, and glass from local artists is used to make an innovative, and glittering, pavement. Concrete elements for the entrance area are casted 5 km from the site and the granite is sourced in a quarry 10 km out. Local biotopes are planted in the landscape, strengthening the native biodiversity. Local produce is prepared in our kitchens and served in the restaurant. We also like to do our share, which is why we produce energy on-site, purify our own water and grow some of our own greens.

Locally Sourced Stone
Bornholm is an island of granite, and the only place in Denmark where you’ll find exposed bedrock. Granite is used in the Green Footprints Park and parking lot, and because it is a local material, it both minimises transport and strengthens local production. With the quarry located just 10 km away, it’s as local as can be! When granite is cut, there is always waste stone – from big chunks to sharp chips and dust. SLA’s approach was that no granite should go to waste, and therefore the design uses it in all sizes and shapes. In the parking lot, both chips and stone dust are made useful.

Hot Water Reservoir
The hotel’s old swimming pool was re-purposed into a thermal energy storage system, storing up to 80000 litres of hot water from the on-site solar thermal plant and any excess energy from the pyrolysis plant. During the summer months our on-site generation systems – pyrolysis and solar thermal – together with the storage system, meet all the hotels needs for heating and the production of potable hot water. The re-purposed pool is insulated and equipped with heat exchangers to maintain the desired temperature of 80°C. The system’s capacity acts as a buffer to meet the overnight heating and hot water requirements when no solar thermal energy is available. During the winter, when daylight for the solar thermal plant is limited, the storage system runs at about 40°C, maintained by a heat pump. The low temperature heat is used for in floor heating in the conference center and preheating potable hot water.

On-Site Energy Production
At Green Solution House we produce energy. Solar cells integrated into the façades and glazed ceilings generate electricity. Our on-site pyrolysis plant converts organic waste to electricity and heat. Additional hot water is generated with a solar thermal plant integrated into the landscape. Since it was not economical to renovate the 30 year old swimming pool, we converted it into a highly insulated energy storage system for excess heat. The solar thermal plant and excess heat from the pyrolysis plant join forces to heat and store water throughout the year, supplying it as needed for in-floor heating and potable hot water for the hotel. To keep an eye on operations, we display our on-site energy production and energy consumption correlated to building zones, with a custom energy visualisation. In the case that we generated surplus energy at Green Solution House it is supplied to the Bornholm grid, meaning our electricity meter can run backwards.

Gaia Solar Cells
Our solar balconies generate electricity and let in more daylight! During the retrofit of the main building, all balconies were changed from concrete to glass and those on the south façade were equipped with photovoltaic cells. Now the solar balconies produce an extra 5000 kWh of energy per year for the building. In addition, the glass balcony railings let significantly more daylight into the hotel rooms than before.

Energy From Waste - Pyrolysis Plant
All food scraps and organic materials from the main building are fed into our own stationary pyrolysis plant. The process
heats the waste, breaking it down to produce natural gas and biochar, which is valuable as a soil additive for the gardens.
The gas is combusted in a combined heat and power engine, generating heat and electricity for the building. Excess heat is
stored onsite as hot water in a swimming pool, re-purposed as a thermal energy storage system.

Water Cycle - Biological Water Purification
Water from the sinks and toilets in the main building is collected and flows through anaerobic, clarifying, and biological filtering stages to enable onsite reuse. The first stages of purification are hidden below ground, after which the system emerges into view and is assisted by sunlight and LED lighting. Here, the water flows through algae tubes that absorb CO2
and continue the water cleansing process. The ambition for the system is to obtain drinking water quality through the biological purification process.

Green Wall - Natural Greenwall System
A large green wall integrated into the Third Climate Zone helps create a good microclimate, thanks to the plants’ natural
ability to freshen the air, stabilise humidity levels and cool the space in summer time. The wall is planted with ferns, which are chosen due to their prevalence in the surrounding nature on Bornholm.

Glass Paths
A one-of-a-kind experiment. Glass paths are very fitting for Bornholm, since the island is well known for its glass production. A local glass artist, Pernille Bülow, donated 12 tons of glass to Green Solution House, which was used to make a paved walking path in the Green Footprints Park. The glass was tumbled in a cement mixer to soften sharp edges sharp edges before being applied as a smooth and glittering glass path.

Recyclable Facade - VELFAC Windows
Save energy and reduce waste. Is it too good to be true? Firstly, the north and south façades of the renovated building
are triple glazed, saving over 50000 kWh compared to the pre-renovated façade. Secondly, they are designed for disassembly. This means that after a very long life in the building, the aluminium window frames by VELFAC will be taken
apart and recycled.

Gabriel Fabrics
New context, new life – sometimes that is all you need to keep functional products out of landfill. Directly transitioning products into new life cycles is the most effective way of minimising virgin resource and energy consumption. Even conventional recycling consumes significant amounts of energy in order to feed materials back into production. Therefore, at Green Solution House, much of our existing furniture stayed in place and was reupholstered with Gabriel’s environmentally friendly fabrics.