CRAVEzero – The Role of life-cycle costs in NZEB projects
Submitted by Baerbel Epp on February 4, 2020 on solarthermalword.org
How much does it cost to construct, run and maintain a Nearly Zero Energy Building? What energy efficiency and renewable options could work best for a given project? Answering these and other questions is the aim of CRAVEzero.eu, a new, interactive online platform. It supports architects and planners during the design and construction process by offering a set of software tools to estimate how much money will be needed for a Nearly Zero Energy Building (NZEB) over its lifetime. One of the properties that have been analysed as part of CRAVEzero is Isola nel Verde, a block of flats in Milan, Italy (see image). Image: Isola nel Verde “We carefully examined the cost structure and planning processes of 12 NZEB demonstration projects in Austria, France, Italy and Sweden to identify a cost base for the purchase, maintenance and operation of different components, including heat recovery systems, solar thermal installations and building envelopes,“ said Tobias Weiss, who works as the project manager of CRAVEzero at AEE INTEC based in Austria. The lessons learned from implementing these showcase projects, which focus on multi-storey residential and office construction in Europe, have since been shared with the entire sector. “Using real-world data from these demonstration projects, we carried out calculations for half a million variants, which you can search for online by going to the Interactive Case Study Dashboard,“ explained Weiss. The dashboard can be found on the CRAVEzero Pinboard, a web page that is currently being beta-tested and includes a number of tools offering support for planners of NZEB projects.
This chart shows the life-cycle costs of different variants for Isola nel Verde in Milan, Italy, in relation to their specific primary energy demand. Combinations which are subject to the same efficiency standards for building envelopes, heating and ventilation, and solar energy systems are highlighted in the same colour. For calculation purposes, it was assumed that loans would run for 25 years and carry 3 % interest at 2 % inflation and a nominal discount rate of 3 %. Source: CRAVEzero The chart above shows the life-cycle costs (LCC) of hundreds of variants for Isola nel Verde in Italy. Specific costs range from 2,800 to 3,600 EUR/m2 (factor: 1.3). The cost estimate for the actual building was 3,615 EUR/m2, split between 1,899 EUR/m2 (53 %) for the building itself and 1,716 EUR/m2 for its operation (energy, maintenance and similar). Regarding primary energy demand, some variants even differ by a factor of 2. If Isola nel Verde had been constructed in line with common building regulations, which require the addition of an air source heat pump (green dots) but no ventilation system, primary energy demand would have been somewhere between 140 kWh/m2 and 210 kWh/m2 a year. The most environmentally friendly variants include 72 m2 of solar collector area and a 14 kWp PV generator (purple dots) and reduces yearly primary energy demand over the entire lifetime of the building to about 100 kWh/m2. Dashboard for benchmarking project LCCs “Calculating LCC variants is therefore a vital step in the integrated planning process of zero-energy buildings. Else, you run the risk that architects and engineers optimise components with only their specific area in mind and lose sight of shared goals,” said Weiss. Variants including solar thermal systems (see the purple dots in the chart above) have the lowest life-cycle costs of all Isola nel Verde options. These systems may lead to a slight increase in the initial investment amount but will save annually increasing amounts of money because of rising energy costs over the 20-year lifetime of a collector. For example, in Europe, up to 50 % of the copper that is used as a key material to make solar thermal circuits can later be recycled. According to the European Copper Institute, recycling reduces energy consumption by up to 85 % compared to primary production. Dashboard users can filter by building envelope, efficiency standard and heating or air conditioning system to find variants. “A great plus of the dashboard is that it lets you compare your building project with the variants available online, so you can see where you stand regarding life-cycle costs, as well as heat and primary energy demand,” explained Weiss. Integrated design The Case Study Dashboard is one of several functions provided by the CRAVEzero Pinboard. Another website feature is the Interactive Process Map, which shows the design process of NZEBs. Integrated design is essential to their construction; in this context, integrated means engineers and architects work together closely to develop the most innovative and effective solution for a given project and monitor compliance with standards and practices during its implementation. Process diagrams are then used to help planners set out the responsibilities of each partner in the project, plus point out possible bottlenecks or weaknesses which have hampered previous endeavours.
CRAVEzero project website: http://www.cravezero.eu
CRAVEzero Dashboard: https://www.cravezero.eu/pinboard/Dashboard/DBInfo.htm
Interactive Process Map: https://www.cravezero.eu/pinboard/PMap/ProcessMap.htm
CRAVEzero Talk4Experts in Austria/ Salzburg – 7.11.2019
Energy Lunch Graz Austria – CRAVEzero / 17.09.2019 /Open News
CRAVEzero @ SBE Conference 2019
CRAVEzero: Special Issue of Journal “Nachhaltige Technologien”
The CRAVEzero Consortium is responsible for an edition of the journal “nachhaltige technologien” about life cycle costs of buildings.
There are costs for constructing buildings, but there are also costs with regard to the whole life cycle of a building. Defining the life cycle of a building different periods can be determined: the production of building materials (building products), the construction and utilisation period as well as the disposal period. Currently, if buildings are planned, the construction period is well considered, whereas the utilisation period is considered unsufficiently and the disposal period often is neclected.
According to the European Commission 50% of the produced materials and energy consumption and a third of the water usage account for construction and usage of buildings. Moreover the building sector is responsible for about 30% of waste (construction, usage, renovation and dumping of constructing materials.
Therefore it is very important to consider all these aspects to a much higher extent in future. Requirements for sustainable buildings can be realised as soon as economic, ecologic and health aspects are considered within their interdependency. The current issue of „nachhaltige technologien“ deals with integral planning with regard to building life cycles and addresses innovative and interesting approaches.
Pinboard beta version for testing is now online
Visit the pinboard here:
The “CRAVEzero pinboard” – an interactive web-based structured framework supporting in developing low LCC nZEBs is online in a first beta version.
CRAVEzero pinboard is a structured framework organizing all needed information and tools to build:
- an effective low life cycle cost nZEB business model
- reliable lifecycle cost databases with cost reduction potentials in processes and
- technologies methodologies, robust solutions and business models for low LCC NZEBs.
Visit the pinboard here:
CRAVEzero @ International Student Energy Summit 2019 in London
Essam Elnagar presented the CRAVEzero project at the International Student Energy Summit 2019 at the Imperial College in London.
The International Student Energy Summit 2019 is an interdisciplinary summit created for students, by students. Over the course of four days, 650 delegates from all corners of the world attended the conference encompassing industry & technology, society & environment, markets & finance, and youth empowerment.
Special CRAVEzero Session @ SBE Conference 2019
CRAVEzero@sbe19_graz: meet us on Thursday in Graz and take part in our 2 special sessions on next generation nZEBs with contributions from our partners Fraunhofer ISE, EURAC and AEE INTEC(more…)
Results of optimised nZEB parametric models
Already today buildings can be realised in the nearly zero and plus energy standard. These buildings achieve extremely low energy demands and low CO2 emissions and can be operated economically. For this reason, the motivation in the CRAVEzero project is not only based on the energy characteristics of buildings, but also on their life cycle costs. However, the broad market deployment of these buildings is progressing very slowly so far, as methods and processes for the cost-optimal integration of efficiency measures and renewable energies are not yet sufficiently described and therefore not yet familiar. As a consequence – many poorly planned buildings are criticised for the fact that the actual energy consumption of highly efficient buildings is higher than the predicted demand and that high-efficiency standards are expensive and uneconomical. The influence of the user behaviour of such energy-efficient buildings is another aspect, which has to be considered to evaluate the impact on the energy consumption of the building.
The identification of suitable methods for the energetic-economic optimization of highly efficient buildings in all life cycle phases is a prerequisite for the broad market implementation.
This method was developed earlier in the CRAVEzero project and documented in Deliverable D6.1 “Parametric models for buildings and building clusters: Building features and boundaries”.
In this Deliverable D6.2, the method was applied to the five CRAVEzero case studies Aspern IQ, Alizari, Isola Nel Verde, Les Heliades and MORE to perform parametric calculations and to perform multi-objective energy and cost analysis over the life cycle of the buildings.
In total, more than 230,000 variants were calculated and analysed, with the key performance indicators: financing costs, net present value, balanced primary energy demand and balanced CO2 emission. The calculation results can be found in this report as well as on the CRAVEzero pinboard: http://www.cravezero.eu/pinboard/Dashboard/DBInfo.htm(more…)
CRAVEzero @ Sustainable Places 2019 Conference
The CRAVEzero project was showcased in the Sustainable Places 2019 conference in Cagliari. The conference involves designing, building and retrofitting the places we live and work in a more sustainable way. Sustainable Places prides itself on being an ideal platform for the dissemination of research, the conduct of workshops, EU project clustering and networking between stakeholders of all types. Between opening and closing keynote sessions, parallel technical sessions and project-organized workshops are held on conference topic areas.