Nederlands
English
10-10-2022
Obligation energy label C: avoid fines
Office buildings larger than 100 m2 must have energy label C or higher from 2023 according to the law. If the office building has energy label D or lower from that year, you as the owner of it risk a fine of up to 81,000 euros or you have to close the building. Prevent this by applying one or more of these five sustainable solutions.
1. Solar panels
Generate your own electricity with solar panels. You can easily generate 170 kWh per m2 of solar power annually with solar panels. The payback period for solar panels is on average seven years. There are schemes that make both the purchase and use of solar panels attractive, such as the netting arrangement and tax benefits.
2. Insulate
Make your office building more energy efficient with wall, floor or roof insulation. There's a number of options:
Cavity wall
If your office building has cavity walls, fill the space between the two walls with insulation material. According to Pim Nusselder, energy expert at Milieu Centraal, cavity wall insulation is one of the cheapest and easiest ways to insulate. “By comparison: with a house you save, depending on the size, between 1,000 and 1,500 euros annually in energy costs. If you compare that to the one-off costs of approximately 5,000 euros, then that is a nice return. You paid for it quickly.”
TNO research institute also sees a lot of potential for savings in cavity wall insulation. It saves a lot on natural gas consumption. Natural gas consumption is responsible for most of a building's energy consumption. Moreover, cavity wall insulation is still relatively little applied, according to research by TNO.
Floor insulation
Does your office have a large floor space? Then consider isolating it. About 10 percent of the energy in a building is lost through the floor. You save about 500 to 750 euros annually. On the other hand, there is a one-off cost of 3,100 euros for a small office. Floor insulation can be recouped in four to six years and it saves you 12.5 m3 of gas per square meter.
Roof insulation
Investing in roof insulation is also a way to reduce your energy consumption, and thus the energy costs. You can choose between insulating material on the inside or on the outside. The most commonly used materials for this are EPS pearls, PUR, PIR or glass wool. The costs of roof insulation are between 80 and 240 euros per m2. Insulating a pitched roof is cheaper than insulating a flat roof. The energy savings are the same: 13.1 m3 gas per square metre. Within an average of five to eight years you will have earned back the investment for roof insulation.
3. Triple glazing
After insulating your roofs and walls, installing better insulating glass is the most efficient thing to do, says Nusselder. “Triple glazing insulates much better than old-fashioned double glazing (thermopane). There is even a big difference with HR++ glass. It involves a lot of square meters, especially in an office building. You lose a lot of heat there, especially between the seams and cracks.”
Wouter Wienk of the RVO also confirms this. “If you are going to insulate, pay extra attention to making the building airtight. Air that leaks out reduces the energy savings of good insulating glass.”
Based on the degree-day method, Wienk calculates the energy savings of different types of glass, opting for maximum yields in an ideal environment without thermal bridges.
“With HR++ insulating glass, you save 31.45 m3 of gas per square meter compared to single glazing. The costs are 150 euros per m2. If you go from double glazing to triple glazing, you will save 3.5 m3 of gas per m2. The major energy savings are mainly due to the renewal of the glass, whereby you also replace the frames. Compared to single glazing you can save 35.0 m3 gas per m2 with triple glazing and new windows. That is a considerable investment: 445 euros per m2 with a payback period of eleven years. But then you do have an airtight framework.”
You can get a subsidy for triple glazing. Pay attention to the conditions: combining different sustainable solutions is often a requirement for this. But if you buy a heat pump in addition to triple glazing, for example, you kill two birds with one stone: you receive a subsidy and you invest in two or more sustainable solutions.
4. Off the gas
See if you can turn off the gas tap. With this option, you take into account the obligation that applies to 2050. In that year, homes as well as business premises and offices must be free of gas. Two alternatives to natural gas are:
Electric heat pump
With an electric heat pump you get hot water and heating via the electricity network. The complete system of a heat pump varies from 3000 to 17,000 euros, depending on the type of heat pump. Then there is the installation. The payback period differs per type: seven years for an air-to-air heat pump to fourteen years for a groundwater heat pump. Nusselder thinks that the latter option is certainly suitable for office buildings. “With this type of heat pump, you extract heat from the ground in the winter and cool your building in the summer. Another advantage: you are immediately well prepared for the obligation to get rid of gas by 2050. Of course, your building must be well insulated. And crucially: you must have a place on the site around your office building where you can drill into the ground.”
Wienk indicates that you need permission to drill. “Check whether you are allowed to drill at the location. In addition, the design, drilling and management may only be done by BRL-certified companies. This also gives a better guarantee on quality.”
Ready for heat pump
It is also important for a heat pump whether the building is already 'heat pump ready', says Wienk. “You have to be able to heat the building with a low release temperature. This usually means that insulation, good glass or underfloor heating must be present. Only then will installing a heat pump also provide financial benefits.”
Heat network
You can use heat from earth, water and biomass to heat your office via underground pipes. This is called a heat network. Heat networks are already available in various places in our country. The greatest costs of a heat network are in the construction and maintenance of the pipes. Developers pass on these costs in the connection costs for heat receivers. A standard connection costs a maximum of 3,700 euros excluding VAT, with a use of no more than 100 kW and a maximum connection length of 25 meters. For larger connections, the buyer and supplier negotiate the price.
5. Green roof
Making your roof green contributes to making your office building more sustainable, but the energy savings are limited. “Taking a green roof without insulating the roof doesn't work. Earth does not insulate well. A green roof does have extra mass and can therefore absorb solar heat in the summer, keeping the building cooler,” explains Wienk.
Higher efficiency
Are there solar panels on the roof? Then plants provide a higher yield of these panels. Wienk explains how this is possible. “Ideal is a green roof with insulation and solar panels. The green roof has a positive contribution to the yield of solar panels, because they stay cooler. The cool surface improves the electricity production of solar panels, increasing the efficiency by nine to sixteen percent.”
More benefits
With a green roof, you also increase the lifespan of your roof, improve the quality of the outside air, regulate rainwater drainage better and help insects. The costs vary, but on average you pay 64 euros per m2. Some municipalities also subsidize green roofs. This sometimes goes up to 2,500 euros. When installing, pay attention to the maximum weight that your roof can bear.
