Filios Eleftherios, GREENSTRUCT, speaks about BIPV double façade modules and thermochromic glass at the 'Innovative Technologies for EU Buildings Energy Retrofit and Deep Renovation' workshop hosted by RINNO and ENVISION.

1. Innovative
Technologies for EU
Buildings
Energy Retrofit and
Deep Renovation
25th March 2022
These projects have received funding from the EU’s Horizon 2020 research and innovation programme

2. BIPV double façade
module
&
Thermochromic glass
Filios
Eleftherios,
GREENSTRUCT
RINNO project
25th March 2022
This project has received funding from the EU’s H2020
research and innovation programme under Grant Agreement
www.rinno-h2020.eu

3. Innovative technologies for EU buildings energy retrofit and deep renovation
BIPV DOUBLE FAÇADE MODULE
A) a-Si technology
B) C-Si technology
In terms of aesthetics, a-Si glass mimics the natural look of a regular glass panel
while the c-Si glass has visible energy cells. The a-Si PV glass can also come in a
variety of colors and transparency, thus can be used both as coverage for an opaque
building envelope with zero transparency and as a fully transparent building
element like regular glasses. c-Si PV glasses on the other hand, have higher yield
resulting in higher amounts of energy production. More specifically, a-Si glass
produces 40-60 W/m2 and c-Si glass produces 120-140 W/m2.
During the course of the Rinno project, we are going to manufacture and implement an innovative installation method for pv double façade
that includes aluminium frame profiles coupled with the pv glasses at the manufacturing facility and hanging brackets on the building that
are going to speed up the process of the installation on site.
These aluminium frame profiles are going to be manufactured with an extra function of facilitating if needed the installation of an
insulating material on the back of the glasses and all the materials together are going to be hanged on the brackets. By using the system
with the hanging brackets, we are able to reduce the time and cost of the total construction process.
The process of glass cladding and connection will be optimized for faster installation and replication in many different types of
residential buildings bringing it fully to residential market (TRL9).
A key issue that can affect installation times and thus disturbance and resulting costs during renovation (regardless of the utilization of a-
Si or c-Si glass), is the efficiency of the installation process. The typical and most used case of installing a PV double façade is by
installing aluminum profiles all across the building façade, then installing aluminum components on these profiles and finally installing the
PV glasses .
In RINNO, instead of following this process, a new installation method will be developed and applied, unlocking a much easier and faster type
of installation by preassembling all the PV glasses along with the aluminum profiles in the factory and hanging them on site in the metal
brackets installed on the building’s façade.

4. Innovative technologies for EU buildings energy retrofit and deep renovation
THERMOCHROMIC GLASS
Thermochromic glass is a newly developed technology that uses the sun heat to darken a glass pane in order to cut off all the
harmful elements from entering a building.
The core principle is that when the temperature on the surface of the glass rises, a thermochromic layer inside the triplex
glass reacts and darkens resulting in a tinted glass while keeping the visibility at all times.
Up until now every glass surface in a building had a standard tint or no tint at all resulting in fixed technical properties
such as G value, solar heat gain coefficient etc.
This means that if we want to have a well insulated glass surface, we must use a very dark tinted glass in order to block sun
heat and all the damaging rays. But this tinted surface remains the same throughout the year resulting in minimized view as
well as rejecting the desirable sun heat in winter times which is the most important.
By using thermochromic glass we allow the sun heat to enter our building in winter and autumn and heat it up properly and
rejecting the sun heat in summer creating that way a building that is self regulated in terms of energy allowance and
rejection.
Most of the user cases of these technologies are large workplace projects and research institutions due to the high initial
acquisition price of the technology.
During the RINNO project we will install this technology in a small residential project in order to showcase the benefits of
the use of such dynamic glasses as well as monitor indoor microclimate and obtain a clear picture of the huge improvement in
occupant’s lives

5. Innovative technologies for EU buildings energy retrofit and deep renovation
Technology Presentation - BIPV DOUBLE FACADE MODULE
Technology BIPV DOUBLE FACADE MODULE
Partners involved None
Technology Short
description
BIPV DOUBLE FACADE MODULE will be a new way of installing photovoltaic
glass technologies into building’s facades. It will be prefabricated
at the factory including aluminium frame, bipv units and optional
insulation panels resulting in a ready to install to the hanging
brackets of the building, module.
Innovation The typical and most used case of installing a PV double façade is by
installing aluminum profiles all across the building façade, then
installing aluminum components on these profiles and finally
installing the PV glasses. During RINNO a new installation method will
be developed and applied, unlocking a much easier and faster type of
installation by preassembling all the PV glasses along with the
aluminum profiles in the factory and hanging them on site in the metal
brackets installed on the building’s façade.

6. Innovative technologies for EU buildings energy retrofit and deep renovation
Technology Market Potential - BIPV DOUBLE FACADE MODULE
Sector Application BUILDING INTEGRATED PHOTOVOLTAICS
Result's Time to Market
at the end of the project
Target Market FACADES, WINDOWS, SKYLIGHTS, BALUSTRADES
Market size and relevant
trend
The global building-integrated photovoltaics market size was valued at USD 14.4
billion in 2020 and is expected to expand at a compound annual growth rate
(CAGR) of 20.0% from 2021 to 2028. Crystalline silicon technology dominated the
market with a share of over 70.0% in 2020. This is attributed to its superior
resistance to adverse weather conditions and high strength. The global market is
expected to be driven primarily by the declining price of crystalline silicon
cells, which, in turn, is expected to lower the installation cost over the next
seven years.
The growing demand for thin-film modules specifically for windows is likely to
strengthen the segment growth over the forecast period. The segment is likely to
witness above-average demand on account of thin-film manufacturing from
lightweight and flexible materials, its strong durability, and narrow design.
However, higher-grade silicon films offer enhanced space efficiency as compared
to thin-film technology, thereby restricting segment growth.
Potential customers Developers, Construction Companies, Home owners, Architects
Benefits to Building
owner/residents/tenants/o
ccupants or other
stakeholder group in the
renovation value chain
BIPV not only produces on-site clean electricity without
requiring additional land area, but can also impact the
energy consumption of a building through daylight
utilization and reduction of cooling loads. BIPV can
therefore contribute to developing net-zero energy

7. Innovative technologies for EU buildings energy retrofit and deep renovation
Technology Presentation – Thermochromic Glass
Technology THERMOCHROMIC GLASS
Partner involved None
Technology Short
description
Thermochromic glass is a newly developed technology that uses the sun
heat to darken a glass pane in order to cut off all the harmful
elements from entering a building.
The core principle is that when the temperature on the surface of the
glass rises, a thermochromic layer inside the triplex glass reacts and
darkens resulting in a tinted glass while keeping the visibility at
all times.
Innovation Up until now every glass surface in a building had a standard tint or
no tint at all resulting in fixed technical properties such as G
value, solar heat gain coefficient etc.
This means that if we want to have a well insulated glass surface we
must use a very dark tinted glass in order to block sun heat and all
the damaging rays. But this tinted surface remains the same throughout
the year resulting in minimized view as well as rejecting the
desirable sun heat in winter times which is the most important.
By using thermochromic glass we allow the sun heat to enter our
building in winter and autumn and heat it up properly and rejecting

8. Innovative technologies for EU buildings energy retrofit and deep renovation
Technology Market Potential – Thermochromic Glass
Sector Application THERMOCHROMIC GLASS
Result's Time to Market at the end
at the end of the project
Target Market
Windows, Skylights in residential, workplace, healthcare,
hospitality sectors
Market size and relevant trend
The global smart glass market size was valued at USD 4.5
billion in 2020 and is expected to expand at a compound annual
growth rate (CAGR) of 6.8% from 2021 to 2028. The emergence of
energy-conservation initiatives, such as green buildings and
eco-friendly structures, globally is expected to offer
promising growth prospects to the thermochromic glass market.
Potential customers Developers, Construction Companies, Home owners, Architects
Benefits to Building
owner/residents/tenants/occupants
ccupants or other stakeholder
stakeholder group in the
renovation value chain
The main advantage of thermochromic window technology is in
the control of heat gain inside a building and a reduction of
glare based on the level of light outside. This type of glass
allows natural light to enter while automatically providing
protection against heat and glare.

9. Innovative technologies for EU buildings energy retrofit and deep renovation
Conclusion
Buildings throughout Europe are quickly falling behind in technology advancements and
many of them are lacking even older thechnologies that could benefit the energy
management and conservation.
On top of that, companies are producing innovative technologies everyday that are hard to
be reached by regular homeowners or investors whether because they don’t comprehend
these technologies or because they can’t fund the necessary replacements.
RINNO project and all other similar projects in the past and future, are the absolute
necessity in order to showcase new eco friendly and advanced solutions to people from
different sectors in order to adopt these solutions and advance the already aged buildings
stock to a new level of sustainability and green technologies.
Filios Eleftherios
lfilios@greenstruct.gr

10. Thanks
for Your
Attention
!
These projects have received funding from the
EU’s Horizon 2020 research and innovation
programme