Right now, the hottest topic on BUILD UP is the nearly zero-energy building (NZEB), as Member States work towards defining NZEBs in the national legislation. At the same time, there are many demonstration projects – in residential, commercial and historical buildings – showing the transition to a smart, low energy built environment.
Here you can download the PDF version of this Overview article (see below under 'Additional documents').
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Legislation and National Applications
The Recast EPBD is, of course, the main legislative driver behind NZEBs. With the national plans for increasing the number of nearly zero-energy buildings (see EPBD Recast article 9 (1)) having to be delivered by September 2012, most Member States are currently busy working on their national application of the definition fixed in article 2 (2). On the BUILD UP Community 'Nearly zero-energy buildings', you will find the most up-to-date information on the national applications published to date, plus the best overview of how the Member States plan to deliver on this ambitious legislation.
As a general introduction, the Concerted Action EPBD team has done some excellent work on charting the development of NZEB definitions across Europe: The Path towards 2020: Nearly Zero-Energy Buildings.
In regards to published national definitions - Denmark leads with a straightforward approach, setting two maximum energy values (one for residential buildings and one for non-residential buildings) with allowances for some specific usages. Read all about Bygningsklasse 2020.
Belgium (Brussels-Capital Region) has also published a NZEB definition. This approach is based on four requirements - maximum primary energy use, maximum heating energy demand, minimum airtightness of the building envelope and maximum number of overheating days. The maximum primary energy use of the building depends on the type of building (residential / non-residential buildings). For non-residential buildings the maximum primary energy use is also dependent on the surface-to-volume ratio. An additional energy performance requirement for non-residential buildings is a maximum cooling energy demand.
Real World Examples
Baffled by ‘legalese’? Overwhelmed by challenge and complexity? Take a breath and then check out the incredible range of application of nearly zero-energy buildings in the Case Studies section. Is it possible to deliver low-cost NZEBs? Yes, it is, say the project leaders of affordable passive housing units (officially opened during the EU Sustainable Energy Week 2012 in Brussels). Are 20-20-20 goals setting an impossible deadline? Not according to this Dutch housing developer, who has produced a design for a net-positive energy dwelling that can be built within just two months – and at an affordable price.
In the office world, Portugal is demonstrating world-class expertise in nearly zero-energy buildings with SOLAR XXI: A Portuguese Office Building Towards Nearly Zero-Energy Buildings. There is a direct and simple message from this project: ‘The key to a very low energy building is good use of daylighting, natural ventilation strategy in combination with mechanical ventilation (hybrid), and passive heating and cooling techniques.’
In a very different climate, Finland shows us what can be achieved further north. NZEB office building Ympäristötalo in Helsinki, Finland has a total primary energy use of 85 kWh/m²a – just half of the Finnish energy regulations. And nearly zero-energy buildings can be great for business too – the Boutique Hotel Stadthalle Vienna: a zero-energy balance hotel whose features include LED lighting and solar panels, and proves that investment in sustainability is paying off now, and in the future.
Low energy building is not just for new builds either. For instance, a historical building in Saint-Etienne, France has been renovated to the Passive House standard by using an innovative membrane, a geothermal heat pump and a balanced ventilation system with heat recovery.
Many NZEB events are taking place across Europe – check out the BUILD UP events listing for the latest meetings, conferences and seminars on this ground-breaking topic. A taste of what’s coming up: The AIVC-TightVent conference - Optimising Ventilative Cooling and Airtightness for [Nearly] Zero-Energy Buildings, IAQ and Comfort investigates innovative ventilation aspects for high performance buildings. Meanwhile, the International Conference on Sustainable Construction and Energy Efficiency invites you to come to Bucharest to debate how the new provisions of the European Directives applied to the national regulations will affect local construction and similar markets when it comes to building energy efficient buildings. At the PassiveHouse Symposium in Brussels speakers from all over Europe will share their knowledge, research and experience on topics such as zero-energy projects and passive cooling and heating.
Do you want to be a part of the debate – and the action – on the future of Europe’s built environment? Join the BUILD UP Community 'Nearly zero-energy buildings' today – the low energy (r)evolution starts here!