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Michele De CarliDepartment of Industrial Engineering, | Adriana BernardiCNR-ISAC, Italy |
List of other involved experts and project partners at the end
of this article. |
The market
of Ground Source Heat Pumps needs to be increased and one of the barriers is
represented by the use of this technology in the retrofit of buildings in urban
environments. For this purpose, the H2020 project GEO4CIVHIC has been funded
and is currently running. The project develops several solutions for shallow
geothermal energy in the retrofit environment, based on the building type,
climate and the geological conditions of the underground and considers all
aspects of the geothermal system (drilling methodology, ground heat exchangers,
grouting, heat pumps). The main objectives are:
· identify and where missing develop modular solutions in drilling (machines and methods) and installing (narrow and reduced spaces), heat exchangers types, heat pumps and other renewable energy/storage technologies, heating and cooling terminals with the focus on each type of built environment (civil and historical);
· generate and demonstrate the easiest to install and cost-effective geothermal energy solutions using and improving existing and new tools.
· Demonstrate the environmental respect and the reduction of CO2 emissions in the atmosphere
More
efficient ground heat exchangers and cheaper drilling methodologies/machines
adapted to the built also narrow environment like the historical centers will
be realised. This approach will bring to an easy applicability in the building
refurbishment presenting different constraints, to reduce the overall drilling
cost in the given geological conditions, to fit in different levels of retrofit
(partial or deep). For better meeting the different needs of the retrofitted
buildings 6 prototypes of heat pumps will be developed and built up, from high
temperature heat pumps (when heating terminals are maintained) up to plug &
play solutions (for deep retrofit), thus reducing the retrofit costs.
The
association of the innovations with different tools like a Decision Support
System will enable to find the best solution for each combination of building
type/climate/geology to be chosen. Moreover, the design tools will reduce
overall engineering costs, avoid design mistakes and form the basis for a major
dissemination effort. Application tools will help the users for different
practical aspects.
The new
solutions in the project will be demonstrated in 3 pilot facilities, in 4 real
demonstration sites (warm, mild warm, mild cold and cold climates) and in 12
virtual sites. Demonstrations go from partial to deep renovations and include
historical buildings.
The H2020
project started in April 2018, lasts 4 years with an overall budget of 8.36 M€,
accounting 19 partners from 10 countries.
The
building retrofit market today barely reaches 1 % of the actual building stock
[1]. In addition, the interventions are of shallow nature in the majority of
the buildings. The Energy Transition initiative of the European Commission is
focusing on increasing the retrofitting of the building stock from the current
1 % level to 3 % and to shift the nature of the interventions towards deep retrofits.
The Energy Efficiency call topics EE-10-2016 (accelerated and cost-effective
deep renovation) and EE-11-2016 (overcome deep-renovation barriers) are the
steps in this direction. The present call topic is one further step of many in research
and innovation to increase shallow geothermal applications in buildings in any
kind of constrains, internal (high temperature terminals) and external (narrow
or difficult to attain free spaces). The revision and implementation into legislation
of the EPBD, the Energy Efficiency Directive and the Renewable Energy Directive
by the EC, coupled with financial support mechanisms (e.g. tax reductions for
deep retrofits, premiums for renewable energy systems) will contribute as well.
The
application of shallow geothermal installations in the built environment is not
well developed [2] at today. The main barriers are:
1. higher upfront investments compared to other
conventional solutions like condensation gas boilers for heating and direct
expansion systems for cooling;
2. difficulties of cost effective and environmentally
friendly drilling in the built environment;
3. need to change Heating and Cooling (H&C)
terminals in order to adequate performance from heat pumps, particularly in
historical buildings;
4. low levels of awareness on the techniques
and its advantages, reluctance to risks and/or lack of experience amongst the
designer and operators (architects, installers, building owners) in the
ultra-conservative building industry.
To overcome
the above barriers, the total investment cost of geothermal systems has to
decrease compared to alternative solutions. The high drilling cost needs to be
tackled. Drilling with highly efficient but heavy and large drilling machines
is difficult and often impossible in the built environment, in particular in
the historical centers. The use of smaller, less powerful machines leads to
even higher drilling costs.
Increasing
the thermal efficiency of the Ground Source Heat Exchangers (GSHEs) is another
way to reduce the total length of GSHEs to install. Ample research in this
field has been done [3], [4] and is ongoing as part of the H2020 projects
Cheap-GSHPs [5], GEOTeCH [6] and GEOCOND [7]. These developments have to be
integrated and/or taken one step further. Development of the Heat Pumps (HPs)
towards a higher efficiency with any kind of terminals and lower costs should
also contribute to the decrease of the total investment or the increase of the
overall efficiency. HPs with good performance at higher temperatures avoid the
need to replace all or part of the heating terminals [8], [9]. Hybrid heat pumps,
i.e. dual source (air to water and water-to-water) HPs can reduce further the
total length of GSHE needed [10]. The combination with other Renewable Energy
Sources (RES) as solar could improve the return on investment [11] [12].
Shallow geothermal systems are more complex to realize than conventional
solutions, in particular when barriers and constraints are present. Critical
aspects include correct design, adequate performance in operation and costs for
the installation. Providing tools, training material/support to designers, instruct
installers and operators facilitate the realization of geothermal
installations, reduces costs, improve the awareness and overcome reluctance
towards this technology.
The project
aims at reducing these gaps and increase the operating efficiency making
shallow geothermal one of the standard applications in retrofitting. The stable
nature of geothermal as a renewable energy source, the ability of heating/cooling
with only one system and the higher residual value of buildings retrofitted
with this technology are additional key factors for investors who are focusing
on the long-term value of retrofits.
The main
goal of GEO4CIVHIC proposal is to tackle all of the above-mentioned areas by
developing and demonstrating more easy to install in any reality and more
efficient GSHEs, using drilling machine innovations tailored for the built
environment and developing
or adapting HPs and other hybrid solutions for retrofits through a holistic
engineering, construction and controls approach.
The present
paper presents the general aspects of the GEO4CIVHIC project showing the
initiatives and the proposed results in the project.
The overall
methodology of GEO4CIVHIC follows a holistic approach with the activities
grouped by type and organized in a logical sequence from research over
innovation to demonstration and evaluation. The communication, dissemination
and exploitation runs in parallel over the four other phases. The all-important
development of the innovations and tools is tackled in the second phase. First,
the basis for driving these innovations and for monitoring the project progress
and results is researched.
Once the
developments have been realized the project moves into an extensive demonstration
phase. Field tests of the key innovations are followed in a third phase by
pilots, full case demonstrations and virtual case studies. Upon results
evaluation, a solid basis is built for market exploitation supported by
training events, workshops and dissemination activities.
Figure 1. The five phases of the project GEO4CIVHIC.
The
consortium partners cover all the important aspects and areas in the value
chain of shallow geothermal plants. The overall work and single tasks have been
organized such that partners work along the main innovation themes in
multi-disciplinary groups.
This
approach maximizes their knowledge, expertise and synergies for the benefit of
the project innovations. phases are shown in more detail below.
Barriers
for geothermal plants in retrofit projects of existing buildings need to be
known to drive the innovation and the subsequent exploitation. They are usually
not only of economic or technical but also social, cultural and legislative
nature. The entire partnership is involved in this task. The partners closest
to the stakeholders (architects, SME’s, industry) use their contacts and
networks.
Geothermal
maps have and are being developed at different scales in European, National and
Regional projects. The “drillability”, understood as the eligibility of the
soil for the best drilling method and the best heat exchanger to use, is not included.
In GEO4CIVHIC this key factor will be added to the maps and guides for later
use in the decision making and the performance evaluation process (including
the traditional drilling methods and the improved technology developed in the
project).
Information
about the cost and performance of heating/cooling plants, including shallow
geothermal ones, is needed to set quantified key performance indicators for the
innovations’ evaluation and to support business models. These plants depend on the
energy demand profile of the building, the heating/cooling terminals and for
geothermal also on the soil. These demand profiles will be generated via
modelling of different building types, building structures, climates and
undergrounds to cover the European market. This is then followed by a cost and
efficiency study.
The
innovation activities in this phase follow respectively a hardware (drilling,
borehole heat exchangers, heat pumps) a middleware (BEMS) and a software track
(decision support, engineering tools, app’s, controls).
The
drilling method, already developed in Cheap-GSHPs for unconsolidated soils, will
be improved using a more powerful and efficient rotation-vibration drilling
head mounted on a compact drilling machine. This to enable to use this
technology in all types of unconsolidated soil and even soft rock. A new head
and the corresponding drilling rig are developed jointly. The drilling rig design
will also address the barriers (compactness, weight, flexibility) and the
reduction of non-productive times. The latter will be done by semi-automated
operator support equipment for fast mounting/dismounting of shafts/casings and
heat exchanger’s installation.
The
efficiency and cost of co-axial heat exchangers can be improved, building on
the developments already realized in Cheap-GSHPs. The powerful drilling head
allows to increase the external diameter but the potentially negative
implications on drilling speed and depth need to be verified as well as the
impact in thermal performance (laminar vs. turbulent geothermal fluid flow) and
pump size/consumptions. An optimization exercise, also with performance data
from Cheap-GSHPs, is foreseen. Other improvements to study are new tube
materials (plastics) and grouts (conductivity), which will come from the
project GEOCOND; in fact, different new grouting and pipe plastic materials are
being developed aimed at further increasing efficiency and decreasing operating
costs of GSHP solutions.
Four new
HPs will be developed based on the analysis of possible HVAC solutions in new
and retrofitted buildings for meeting high and low temperature with one or two
sources. Another HP faces the trend in the market to move to smaller-size heat
pumps suitable for the retrofitted buildings with low energy demand (nZEB, ZEB
or PEH). A compact geothermal heat pump, easy to install and to integrate in
existing buildings, will be developed. Finally, a low temperature HP with mid-term
low GWP fluid will be also developed.
The
development of a middleware solution regards the connection between the HPs and
the other RES like solar thermal, PV or wind and allows the interaction and
coordinated control of these technologies. For this purpose, a development of
intelligent control algorithms, in connection with BEMS, will be made, in order
to increase the overall efficiency of the installations. The last track is
about ICT tools. The Web based Decision Support tool and the engineering tools
to size the GSHEs will be based on the tools developed in Cheap-GsHPs and will
be improved during GEO4CIVHIC. The repository with solutions for drilling, heat
exchangers, HPs is built in first period of the project using the knowledge and
experience from the partners in each of their areas of expertise. The tool will
then be adapted for any kind (civil and historical) retrofitted building
applications.
Moreover
the “drillability” guide and geothermal maps will be carried out for helping
users in the selection of the most appropriate drilling method and heat
exchanger choice.
The
demonstration phase is the moment of truth, where the innovations have to be
checked and tested. A cascade of test and demonstration sites is set up, having
specific innovations to validate. The pilot facilities are sites where specific
innovations are tested and improved, while demonstration facilities are sites
where buildings are retrofitted and the GSHP solutions of GEO4CIVHIC are
installed. In the Figures below the 3 pilot facilities and the 4 demonstration
facilities are shown with the related innovations descriptions. The pilot
facilities are intended to check and test some specific technologies which are
developed during the project (3 prototypes of HPs, 3 co-axial solutions,
innovative materials and better coupling with RES). The demonstration
facilities are supposed to be used to check the retrofit (shallow or deep) of
the buildings with installation of 4 different prototypes of HPs (different
also from pilot facilities) and two different solutions of co-axial pipes.
Overall 7 prototypes of HPs will be developed, 3 types of co-axial and one type
of very shallow GSHEs will be developed and tested.
Pilot facility n. 1 (CNR), Italy3 innovative small size HPs, together with
novel co-axial pipes solutions | |
Pilot facility n. 2 (TECNALIA), SpainInnovative small size HP + RES and
testing/optimization of BEMS | |
Pilot facility n. 3 (UPV), SpainVery shallow heat exchangers, special grouting
and new materials for pipes |
Figure 2. The three pilot facilities which are used in the project.
Demonstration facility 1Malta (warm)Co-ax GSHE + HP prototype n. 1 | |
Demonstration facility 2Italy (mild warm)Co-ax GSHE + HP prototype n. 2 | |
Demonstration facility 3Belgium (mild cold)Co-ax GSHE + HP prototype n. 3 | |
Demonstration facility 4Ireland (cold)Co-ax GSHE + HP prototype n. 4 |
Figure 3. The four real demonstration facilities which are used in the project
In both
pilot and demonstration facilities monitoring campaigns will take place and
models will be run in order to have a better understanding of the problem by
tuning them and finding general results (e.g. not influenced by the actual
climatic conditions but referenced to average climatic conditions). Results of
real demonstration facilities will give not only the performance of the proposed
solutions, but also the installation costs and the possible problems in using
the drilling machine and the installation of the GSHEs. Costs and problems also
of the building retrofit will be useful information to look at.
During the
development and demonstration of the new technologies, risk assessments will be
made in parallel and coupled back to the development teams.
Beside the
real demonstration facilities there are 12 virtual demonstration facilities. In
these sites retrofit of buildings have been planned or realized or will be in
progress. The innovations of GEO4CIVHIC will not be installed, but will be
sized and a feasibility study will be carried out. The owner could at a later
stage implement the developed solutions since substantial parts of the engineering
work will have been done. At the same time, the costs and renovation problems
in the building will be used for enlarging the data base of solutions and
cost-benefit analyses.
After the
demonstration phase sufficient information is available to evaluate the cost
and efficiency impact of the different developed solutions. Material costs,
production, assembly and installation costs are known by now and can be
extrapolated towards larger scale application. The benefits and also the
environmental impact can be defined using LCA and LCCA methodologies
demonstrating how these technologies are environmentally friendly and strongly
help in the reduction of the CO2 in the atmosphere.
Several
consortium partners have been participating in previous projects on shallow
geothermal systems covering standards, regulative and legislative aspects. They
will make conformity verifications and possible recommendations on the
integration in standards and regulations for these new technologies.
The fifth
pillar phase, comprises all the horizontal, supporting activities of the
project. It regards the broad and attractive sensitization, communication and
deployment activities aimed at reaching different kinds of stakeholders and
SME’s along the supply chain. Awareness is one of the main barriers for shallow
geothermal systems next to the high upfront capital cost.
Dissemination
and Exploitation take place during the whole project where the GEO4CIVHIC
solutions will be used for specifically targeted exploitation activities by the
consortium with different actions and events during and after the end of the
project.
Moreover,
the training material available during the project will provide precious
available material, not only related to the results of the GEO4CIVHIC project,
but also to the most recent important innovations realised during the last
European projects where some partners were involved. This material will fundamental
to increase familiarity with heat exchangers types and installation, heat
pumps, controls and, as a consequence, can remove fear. The big industrial
representative in the consortium makes possible to develop a realistic and
complete exploitation plan for each step in the chain. An exercise on the
financial incentives, most probably not well known by many stakeholders, will
provide an additional support to the business plans.
Also, the
options to link up with regional structural fund initiatives on RES need to be
included in this modelling exercise. Finally, the cluster with the other
successful projects presents an opportunity to include in the hybrid plant
configurations the latest developments in the other renewable heating and
cooling technologies.
In this
paragraph particular reference to the building types which are going to be
analysed in real and virtual cases will be shown in order to make stakeholders
better understand the problem of retrofitting buildings and to provide suitable
heating and cooling by means of GSHPs.
It has to
be underlined that the key problem to be solved in the project is to provide
more suitable solutions for retrofit of buildings in urban areas. The key point
of GEO4CIVHIC is to look at both existing and historical buildings with
different types of renovation, i.e. shallow retrofit or deep retrofit.
For this
purpose, on one hand the problem will be examined by using archetypes in order
to generalize results (see another paper proposed at CLIMA 2019), on the other
hand the real and virtual cases will provide feed-back on the applications of
the proposed solutions and on the real costs, i.e. costs for retrofitting the
envelope, the HVAC costs and GSHP costs.
As already mentioned,
4 real cases and 12 virtual cases are being analysed in the project. So far the
data collection of the buildings are ongoing and for some of them some
preliminary energy modelling has been carried out.
As could be
seen in the next table, the 16 cases are subdivided in: existing buildings and
historic buildings. Defining historic buildings is not always clear and simple.
I a very simplified way a building can be considered historical when it has
been constructed 50 years back in the past. So we have defined existing
buildings built after 1960 and historic buildings the ones built before, even
if exceptions may occur. As can be seen there is a good variety of buildings as
for the age, being 7 existing buildings and 9 historic buildings.
A further
analysis has been carried out considering also the climatic conditions based on
the classification carried out in Cheap-GSHPs project [13]. The subdivision has
been carried out into: Warm (W), Mild Warm (MW), Mild Cold (MC), Cold (C)
climates. As might be observed in Table 1, the subdivision among climates is
also consistent, dealing with all possible solutions from dominant heating
cases to dominant cooling cases, passing through balanced cases. As a matter of
fact, there are 3 cold climates, 4 mild cold climates, 5 mild warm climates and
4 warm climates.
The work
which is being carried out is providing and will provide a huge amount of
information which needs to be set up in a well-organized data base which needs
to be robust and consistent with the other data sets coming from the other
tasks. All information will be used for the costs and environmental analysis
which will be ready almost at the end of the project.
Table 1. Description of the real and virtual
demonstration sites and subdivision among age and climate: Warm (W), Mild Warm (MW), Mild Cold
(MC), Cold (C).
Location | Age | Climate | |||||
Existing | Historic | W | MW | MC | C | ||
Real | Malta | X | X | ||||
Italy | X | X | |||||
Belgium | X | X | |||||
Ireland | X | X | |||||
Virtual | Greece | X | X | ||||
Spain | X | X | |||||
Romania | X | X | |||||
Romania | X | X | |||||
Italy | X | X | |||||
Croatia | X | X | |||||
Germany | X | X | |||||
Belgium | X | X | |||||
Ireland | X | X | |||||
Switzerland | X | X | |||||
Spain | X | X | |||||
Holland | X | X | |||||
7 | 9 | 4 | 5 | 4 | 3 |
The present
paper shows the general methodology which lays below the project GEO4CIVHIC
which is one of the biggest research activities in the next three years in the
frame of shallow geothermal energy. The project deals with the retrofit of
buildings in urban areas and aim at providing technologies suitable for very
narrow places with important barriers of different kind. All the developments
will go in four main directions:
·
novel
types of GSHEs and drilling technologies;
·
novel
types of heat pumps dealing with low and high temperature solutions and with
one or two sources;
·
middleware
solutions for enhancing the coupling between GSHP solutions and RES;
·
software
solutions for helping designers in sizing and designing GSHP technologies and
to provide more awareness to stakeholders through software and apps;
·
reduction
of the CO2 emission in the atmosphere in a
future sustainable production of energy.
The project
lasts until March 2022, hence results will be ready in the next future. The main
purpose of the present paper is to show also the real and virtual building
cases which are going to be analysed in the project to have a wider overview of
the project and its potentialities.
Most of the
technologies which are going to be developed in GEO4CIVHIC have to be protected
for patent potential applications and hence no further details can be provided
so far for prototypes and machines which are going to be developed and
produced.
This work
has received funding from the European Union’s Horizon 2020 research and
innovation program under grant agreement No. 792355.
Other involved
experts and project partnersAntonino Galgaro,
Department of Geosciences, University of Padua, Italy Gianluca Cadelano,
CNR-ISAC, Italy Francesco Cicolin,
CNR-ISAC, Italy Sergio Bobbo, CNR-ITC, Italy Javier Urchueguía,
Instituto de Aplicaciones de la Comunicaciones Avanzadas (ITACA), Universitat
Politécnica de València, Spain Giulia Mezzasalma,
Red Srl, Italy Riccardo Pasquali,
Terra GeoServ Ltd, Ireland Fabio Poletto, Galletti
Belgium NV, Belgium Amaia Castelruiz Aguirre,
Fundacion Tecnalia Research and Innovation, Spain Amo J. Romanowsky,
ThyssenKrupp Infrastructure GmbH, Germany Davide Poletto, UNESCO, France David Bertermann, Friedrich-Alexander Universitaet
Erlangen-Nuernberg, Germany Robert Gavriliuc,
Company / Institution: Romanian Geoexchange Society, Romania Dimitrios Mendrinos,
Centre for Renewable Energy Sources and Saving, Greece Davide Righini,
Hydra Srl, Italy Burkhard Sanner,
UBEG Dr Erich Mands U Marc Sauer Gbr, Germany Jacques Vercruysse,
Geo Green, Belgium Leonardo Rossi,
Pietre edil Srl, Romania Michele Vavallo,
Solintel M&P SL, Spain Luciano Mulè Stagno,
Din l-Art Helwa, Malta Marco Belliardi, SUPSI,
Switzerland |
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