New European standard EN 50583 determining the parameters of BIPV, the solar power plants integrated with buildings, takes effect in November 2016. Though, at present, the BIPV market share comprises no more than 1%, EN 5083 can change the situation resulting in the boost in building-integrated photovoltaics and change the appearance of modern cities forever.
One needs return in the past for a little to understand what constitutes BIPV in order to determine the extent of the influence that a new standard has on the industry. At the first time, the term “BIPV” appeared in 1970, when the photovoltaic systems reinforced with aluminium started to be integrated with ledges and roofs of buildings. That time the economic viability of building-integrated photovoltaics was lower than the economic viability of typical solar power plants. However, the development of photovoltaic technologies during past years increased their efficiency. The key difference between BIPV and other kinds of solar power plants is that BIPV elements become the integral part of the building, replacing some engineering structures and construction materials. New standard shall regulate this particularity.
Building integrated solar power plants are mounted traditionally on flat and lean-to roofs and are integrated with frontages or elements of glazing: domes, glass roofs, floor-to-ceiling windows. As a rule, BIPV systems are represented by one type of solar panels:
The adoption of the BIPV standard needed more than five years. At present, the approval of its versions by England, France and Germany takes place. The main particularity of the standard is that it details the parameters and the definitions of BIPV, having likened them to usual construction materials.
Before now, when it came to the integration of solar power plants with buildings, there was not a clear definition of this integration mechanism. Now, for the first time in decades of BIPV existence, EN 50583 has put all things. According to the standard, building-integrated photovoltaic panels are these ones, which have to be replaced after their removal from the building by other construction materials or structures in order to preserve the structural integrity of this building. The standard defines clearly the functions that can be performed by solar power plants integrated with the building structure.
The standard also determines five methods of the installation of photovoltaic elements.
Up to now, the manufacturers of BIPV systems did not follow building standards during the production of solar modules. It is quite a paradox: the panels of BIPV systems are used in building instead of other construction materials. As a rule, they replace reinforced glass constructions. European standards regulate scrupulously the use of the vitrifaction, taking into considerations angles, thickness of the glass pane, frames and forms of glazing. However, there was never anything like this for BIPV systems. EN 50583 eliminates this defect, providing the same requirements to BIPV modules, relating to the way of their integration and the durability of the structure, as to the construction materials.
Solar modules, produced up to now, are not adapted in most of the cases for the use under atmospheric aggressive conditions: exposure to wind or snowfall. Glass/foil typical structures are protected by the layer of glass with the thickness of 3 or 4 mm, more modern double glass panels can meet the building standards only by chance. As usual, they are even not tested under aggressive atmospheric conditions. The standards IEC 61215 and 61730, regulating the production of these modules, are elaborated by the International Electro-technical Commission for BIPV crystalline-based modules, taking into consideration their electro-technical parameters (not structurally-mechanical ones).
Though IEC standards define the requirements to mechanical loads of solar modules, the experts of the commission do not detail this aspect. Thus, the explanation of the calculations of wind load value, according to the standard IEC 61730 takes about a half of a standard size sheet A4. For comparison, an analogous standard EN 1991-1-4, applied to building constructions in the European Union, comprises 250 pages. The standard EN 50583 transforms this approach.
Furthermore, the most important aspect of putting BIPV systems into operation, described by new standard, is the specialisation. The solar module integrated with the building frontage at the height of 5 meters shall bear much less axis load, weather effects and wind load than an analogous module mounted on the 50th floor. It is not profitable to use identical modules in the given situation. Thereby there is the necessity of the description of the requirements of various specialised modules. The standard spells out these requirements as the list of ways to fix the modules and the length of bearing surfaces defining the form and the type of module. The compliance with the standards calculated for glass structures helps to specify the parameters of the modules. In fact, the standard integrates photovoltaic panels with the existing operating models for glass frontages, domes and roofs, providing BIPV systems with the importance equal to other construction materials.
As it was mentioned at the beginning of the article, about 99% of the solar power plant market are not subject to new standard. However, this rate can change in the nearest future. A lot of companies manufacturing solar energy units consider BIPV systems the key to the future market, which will start growing at the moment when the price of solar panel integration is lower than the price of power generated in this way.
Internal initiatives of many countries favour to such a development of events. For example, the decree of the European Council from 2010, regulated energy efficiency in buildings, will take effect in December, 2020. At this moment, households shall comply with the criteria, stipulating practically zero-energy consumption and cover the power deficit from renewable energies. The decree does not list the sources of renewable energy, but there is a high probability that just BIPV systems will become the base of such kind of energy efficiency up to this moment. Even today, much earlier than the decree of the European Council is effective, many cities worldwide integrate BIPV systems with their buildings. Thus, in April of the current year, the steering committee of San-Francisco, California, took the decision on the use of solar power plants in all new construction projects.
The industry of BIPV systems grows, and set ambitious targets. Newly formed group of companies, Allianz BIPV, residing in Germany, aim to achieve just such a goal: make BIPV systems become a recognised component of the process of building. The group includes small architectural and construction companies. Their representatives are certain that BIPV systems will become an integral part of modern architecture in the near future.
Moreover, when large companies decide to join, it will surely occur.