Let’s check: is the energy use of our renovated buildings really improving?
Insulation, solar panels, HR glazing and new installations. All over Europe the existing building stock gets updated to become NZEB, a (Nearly) Zero Energy Building. We’d like to know if these renovations live up to their expectations and which investments are the smartest. Therefore we monitor the energy performance of all buildings within the framework of the City-zen project.
In 2016, DNV GL began investigating the energy performance of the renovated buildings in Amsterdam. The so-called monitoring. This monitoring consists of determining the monthly energy performance for at least one year. We looked at electricity and gas consumption, and the performance of any solar panels. At the beginning of January 2018 there are 48 active addresses where energy data are recorded.
Good results for first two blocks
From 18 addresses, data is available for a whole year. These are a block with rental apartments (huurcomplex 1) and a former school transformed into apartments (verbouwde school nr huizen 5), of which the preliminary results are shown here. The energy performance of these blocks is also known for years before the renovation. This can be compared to determine the savings achieved. For the former school this is not relevant as the use has changed quite a lot.
For the Huurcomplex 1, the measures were:
- A PV system of 139 kWp on the roof
- Thorough insulation of the houses
- High efficiency boiler
The results are a building bound energy consumption of 44 kWh/m2yr. This is a saving of about 71% compared to pre-refurbishment situation.
For the Verbouwde school naar huizen 5, the measures were:
- Good insulation
- Solar panels on their own roof (22.5 kWp) and on a neighbouring roof (30 kWp)
- Heating via heat pumps
- LED lighting
- Demand-controlled ventilation with direct current (energy-efficient) fans.
The result is an energy consumption of only 9 kWh/m2yr which is almost energy neutral.
During 2018 and 2019 more projects will be followed and the monitoring results will be shared. Moreover, Delft University of Technology will look into the link between the actual energy use and the way residents perceive their neighbourhood, sustainability, innovation and their own behaviour. We expect some interesting results from this comparison.
The contact person for City-zen’s technical monitoring is Rudy Rooth (DNV GL)