Principles of a passive bio-ecological energy plus house
A passive house is characterized by a solid building envelope with a thick insulation package and a gap-tight finish. This saves a lot of energy. The concept is simple: the less heat a building loses, the less it needs to be heated. The same, but vice versa, applies to the summer. A "passive" shell is therefore the best financial protection against rising energy prices. Moreover, a good building envelope does something that renewable sources cannot: improve the comfort of the residents. Drafts, condensation, fungi and cold and damp rooms are therefore a thing of the past with a high-performance damp regulated building envelope.
From the design of this house, an integrated concept was maintained in which light, view, experience and energy are a spearhead, resulting in a cost-efficient, low-energy house. This manifests itself in a compact building with a good orientation and a sensible integration of energy technologies such as:
- Mechanical ventilation type E (mechanical balance ventilation combined with heating / cooling and heat pump (air-air)
- Zone temperature settings so that spaces that are temporarily unused consume less energy
- Heat pump boiler of 300 l, which reduces the cost of producing hot water to one third compared to a classic electrical boiler
- Home automation that allows switching off sockets, preventing the energy costs of unnecessary standby currents
- Exclusive LED lighting
- Automatic light switches in the common areas so that the lights do not stay on unnecessarily
- 52 high-efficiency solar panels with 16,5 MWh of peak power that cover the sun all day long ensuring more than sufficient annual energy production to cover the annual energy needs of an average family with two electrical cars
The net energy requirement for heating and cooling for a passive house is a maximum of 15 kWh/m² per year. Insulation, airtightness and ventilation are taken into account, without compensation with renewable technologies.
The PEB (Energetic Building Performance)
Ew value = 14kwh/m² versus the actual required standard of 45.
The K value = 22 versus 35
Through bio-ecological building we want to achieve a healthy mind in a healthy body in a healthy house in a healthy living environment. This by making optimal use of inexhaustible natural raw materials and energy sources, which are locally available as much as possible.
In this bio-ecological house, mainly biological building materials were used with a proportion greater than 90%. The structure of the house, garage and workshop consists of a skeleton of composite FSC wood. The inside / outside finish was realized with MGO (Magnesium Oxide) plates which have a small ecological imprint and are also combustion and moisture resistant, shape-retaining and breathable so that the wood skeleton is protected against fire or moisture damage both inside and outside.
This is one of the first houses in Belgium to be finished with MGO plates.
Furthermore, the house and even the workshop are very air tight with a minimal air loss / hour of 860 m³( V50) for the house as measured by the blower test.
The outer walls and roof of the house are breathable so that the moisture / vapor generated inside is controlled via an intelligent regulating vapor barrier to evacuate vapor towards the outside.
Through the many small windows a lot of light penetrates the rooms, whereby the sun (partially) warms the house during the in between seasons and in winter, but without causing overheating in the summer. (see BEP report)
Two rain containers are provided. The large of 10.000l capturing the water of the house and garage, serves the toilets, the washing machine (s) and the service tap in the garage. The one capturing the rain from the workshop in the garden with its 3000l, can be used for the garden watering. If one of the containers overflows during heavy rainfall, the excessive rainwater will be infiltrated back on the site via two separate drainage canals with a collection capacity of 10m³ and 4m³ respectively. This means that no excessive rainwater is lost as it penetrates immediately into the ground.
The house has its own water purification station so that the used water is returned to the earth after biological bacterial purification. This will prolong the live of the water taps, the water boilers and other water related equipment.
The tap water is purified from particles via a small maze filter and a descaler eliminates the excess of chalk.
Energy plus house
Thanks to the extensive insulation of the outer walls and the roof, the windows / doors with triple glass with their high insulated profiles, combined with the heat pump for heating / cooling and the heat pump boiler, LED lighting and home automation, relatively little electrical energy will be needed for the temperature comfort in the home and the hot water production.
Using the SMA Sunny design web energy simulator, it is calculated that the total annual electricity consumption for a family of 5 people with a daily hot water consumption of 250l and one electric car that drives an average of 70km / day, is approximately 11,6 MWh / year.
The solar panel installation with its 52 high-efficiency solar panels that are oriented to the East, South and West so that a wide electricity production curve is created during the entire sunny day, generates an average of 14,1MWh / year.
Thus 2,5MWh is produced in excess versus there is consumed on an annual basis. So a second electrical car could be fully charged giving you almost free car rides.
Apart from the annual rent of the electricity meter and the pro-consumers tax of 750, € / year for the solar panels, there will be no energy costs for living in this energy plus home. This generates an estimated saving of over € 108.000,€ over 30 years (lifespan of the solar panels). See table below.