Evolution towards the concept of passive houses. Efficient design vision.
Obtaining a good energy rating in a building or home requires compliance with "strict and rigorous" requirements in terms of energy efficiency parameters, since, otherwise, we will remain in an average or "standard" rating, For example, for buildings that are limited to meeting the requirements of the Technical Building Code, it will oscillate between a C or a D and obviously, to exceed this rating, it is necessary to improve in many aspects, not only in terms of the composition of the envelope. thermal is concerned.
For a home to be as efficient as possible, in the case of newly constructed buildings, it is necessary for the designer to go beyond the Technical Code itself, bringing the conception of its design closer to what is conceptually called "passive house", and imposing concepts of bioclimatism, you should try to optimize some basic aspects to the maximum, yes, always evaluating their technical and economic viability based on the energy savings that can be achieved, since the cost of the investment necessary for this case it is much superior to that of a "standard home".
First appearance; Efficient design.
The most efficient design will be the one that allows the building's energy demand to be reduced as much as possible, for which it requires an adequate orientation of the building, a reduction in the surface of the envelope, an adequate percentage of optimal holes in each facade according to orientation, etc. , etc … always trying to adapt it according to the climatic characteristics of the area. We are talking about what we commonly know as bioclimatic design, but the question that arises is Is it always feasible to implement this type of design in any property? obviously NOT, because in many cases our building must be adjusted to a plot with an orientation, we cannot rotate our building to give it the proper orientation, nor can we project gaps in an alignment that according to planning must be a dividing wall, nor can we prevent it from certain obstacles cast a shadow on us if we are talking about neighboring buildings, all in these factors and especially if we are treating a building between party walls, they will be pre-established so that the designer is already conditioned by them, another very different case would be if the building is not between party walls or that of an isolated single-family home where the designer has many possibilities in terms of design and orientation, in these cases there is greater versatility in the design and its optimization is easier in search of a reduction in demand and improvement of energy efficiency.
As a consequence of the above, only one reflection arises, if we seek that a designer can design an efficient building, shouldn't we start from an efficient and sustainable previous planning? That is, from an urban planning that takes into account the position of some buildings with others depending on the orientation and the widths of streets to avoid or minimize the shadows cast, which raises the creation of certain intermediate spaces or green areas and of course with the necessary infrastructure that allows the projection of buildings that can be reused and Make the most of natural resources, as well as that they can be integrated and adapted to the environment and climate of the area to achieve this design, reduce energy demands.
On the other hand, I would like to refer to the construction systems of the envelope itself that must be optimized to allow the comfort conditions inside to be maintained for as long as possible throughout the year, thus reducing its energy consumption, for which I would advocate creating envelopes that are as organic as possible, that is, construction systems through green or landscaped facades or roofs, given the important function that these plant species perform by regulating the temperature and humidity conditions and in the same way other passive systems such as solar chimneys, Canadian wells, glass greenhouses, trombe walls, etc. that will allow us to achieve this comfort without any type of energy contribution.
Second aspect: Energy self-sufficiency with clean energies.
Once the designer has optimized the design of his building and reduced its energy demand to the maximum, he must consider reducing its energy consumption, for which he can choose to cover these energy demands with renewable energy systems and complement them with other DHW equipment, or for example with aerothermal heating, cooling and even lighting equipment that is efficient or that reduces its emissions and minimizes the impact on the environment, always trying to find those energy sources that are not of fossil origin.
Currently, in terms of renewables, the Technical Code requires the implementation of solar thermal energy for sanitary hot water for residential buildings or single-family homes (See news of the Technical Code), however to raise or improve our rating we must continue along the aforementioned path of going further, looking for the path of passive houses by implementing other sources of renewable energy such as photovoltaic solar panels, wind energy, energy geothermal, biomass, or with hybrid systems, trying to make our building self-sufficient with clean energy.
Conclusions:
The replacement and / or elimination of the equipment that currently covers the energy needs of our buildings by others that work with alternative or clean energies may seem something "utopian" or at least far on the horizon, but it will be a way to go if we want improve the energy efficiency of the buildings we build.
The main obstacle that we would encounter when wanting to change or "evolve" towards this more sustainable building model would be that in our country the existing legislative framework in relation to renewable energies and self-consumption does not help the owner who intends to implement this type of installation. for its self-sufficiency and also puts too many trips, taxes and bureaucratic obstacles for it, but this is another topic that I do not intend to deal with in this article, although I do not want to ignore it either. And now I invite you to reflect on the following questions:
Do you consider that it is necessary to evolve in the design of buildings towards a more efficient type of building that encompasses all or some of the precepts of a passive house?
Do you think this change is viable from a technical and economic point of view?
Do you think that in this way we will be on the right track to achieve the 20-20-20 goal set for the year 2022?
… .
Article prepared by José Luis Morote Salmeron (Technical Architect - Energy Manager - Google plus profile) Access to his website HERE, in collaboration with OVACEN.
