Energy self-sufficiency is extremely beneficial for buildings of all types. Can you imagine a situation where gas or gas oil bills are a thing of the past and the only electricity charge is for the contracted power, which in turn is significantly lower despite continuing to make regular use of your electrical appliances, lighting and heating and cooling systems? Well, in the case of nearly zero energy buildings – including private homes or constructions of all types and for all uses, this is now more accessible than ever.
Yet what exactly do we mean by the term “nearly Zero Energy Buildings” (nZEB)? The concept was defined by directive (EU) 2010/31of the European Parliament and of the Council on the Energy Performance of Buildings, enacted with the twofold objective of cutting buildings’ energy consumption (which accounts for 40% of the total in Europe) and reducing the effects of greenhouse gases and other polluting emissions that are the cause of climate change.
In this sense, the directive stipulates that as of 31st December 2020, all new buildings must have a nearly zero energy consumption, a requirement that will come into effect two years earlier in the case of public administration buildings. It defines nZEB as having a very high energy performance, where the extremely low level of energy required is covered to a very significant extent by renewable sources produced on-site or nearby.
nZEB are buildings where design and construction methods are based first and foremost on energy savings in order to guarantee thermal comfort. This includes the use of passive architecture techniques, placing particular attention on the building envelope and its weatherproofing and ventilation control. In addition, the installations and equipment employed guarantee outstanding performance in terms of obtaining the required temperature with the lowest possible energy consumption.
The minimal demand required by nZEB from renewable sources can be supplied by a photovoltaic solar energy system, capable of generating the on-site clean, sustainable and efficient energy needed by the heating and cooling systems and sanitary hot water.
New energy transition and consumer protection regulations that have recently come into force in Spain, which have already been discussed here, have not only done away with the barriers to self-consumption but are also an incentive for both individual and collective energy self-generation in buildings for immediate consumption and the transfer of surplus energy to the grid.
Here at Terravita Renovables we have more than 10 years’ experience in pioneering projects centred on efficient heating and cooling systems as well as renewable energies in nZEB. One such project is Can Tanca, on Ibiza, which is Passivhaus Premium certified by the Passivhaus Institute in Germany.
Passivhaus standards in building energy performance go beyond nZEBs, setting a series of requirements such as a demand for heating and cooling of less than 15 kWh (m2 per year) and for primary energy (heating, hot water and power) of less than 120 kWh.
In the case of Can Tanca, the renewable primary energy required is under 30 kWh, in other words four times less the amount required by Passivhaus building standards. Moreover, it can generate more than 120 kWh of electricity thanks to its optimum photovoltaic solar power self-consumption facility, which is independent from the grid.
Whether it is independent, as in the case of Can Tanca, individual or collective, for immediate consumption or surplus for transfer to the grid…self-consumption power facilities from photovoltaic solar energy are the best solution for nZEBs. At Terravita Renovables we deliver renewable energy-based heating and cooling system solutions tailored to meet the specific demands of all types of nZEBs.