What is Zero Energy Building?
The Zero Energy Building (ZEB) is a building with zero net energy consumption, meaning the total amount of energy used by the building on an annual basis is roughly equal to zero.
The ZEB building uses energy from the grid for heating and cooling purposes. However, the total amount of energy used
by the building is equal to the amount of renewable energy created on the site, usually by integrating photovoltaic cells
on the roof of the building.
The Passive house (passivhaus)
Passive house (passivhaus) it could also be a zero energy building. However, it follows a different philosophy. It is an airtight, highly insulated building that requires little to
no energy for space heating or cooling. Passive Houses make efficient use of the sun, internal heat sources and ventilation with heat recovery, thus making conventional heating systems unnecessary. Heat losses are almost eliminated, in a way that there is only a need for a small heating system and only for
a few days throughout the year.
The passive house standard was established in Germany during the 90's. With approximately 60.000 Passive House buildings
in use worldwide (as of 2016) it is rapidly spreading all over the world. The passive house standard can be applied in both cold and hot/humid climates. The first passive house certified buildings have already been constructed in Greece.
Passive solar design and orientation
Super-insulation of the building envelope
High performance windows
Mechanical ventilation system with heat recovery (MVHR)
Solar thermal and PV systems
Heating – Cooling system
How does a Zero Energy Building work?
Energy retrofits
Existing buildings can be renovated through energy saving measures in order to achieve optimal building performance and reach the Zero Energy Building standards. Turning an existing building into a zero energy one is not an easy task. However, through a focused, detailed planning approach we can reduce the building’s energy consumption up to 90%, thus practically eliminating heating and electricity bills. The whole renovation process can be integrated in a state funded program that can cover up to 70% of the expenses.
What are the advantages of choosing a ZEB?
Money saving
Save money by eliminating your heating and electricity bills. ZEB buildings have reduced net-monthly total costs of living and a short payback period of the initial investment. The extra cost of building a ZEB building compared to a conventional one is around 3-12%, depending on the region.
Excellent indoor living conditions
ZEB buildings combine pleasant indoor temperatures during the cold winter months and hot summer periods, with ample fresh air and high indoor air quality. The mechanical ventilation system ensures fresh air at room temperature at all times. Internal air is free of dust and pollen, while the risk of developing humidity and mold is eliminated.
Sustainability
ZEB buildings help preserve limited resources like gas and oil while having zero CO2 emissions. This makes them friendly for the environment and a contributor to the climate protection. Water and waste management systems can be integrated in the building, while it is possible to use ecological and local materials for the construction.