Aplicación Práctica / Practical Issues
Recibido: 14-10-2024 Aprobado tras revisión: 08-01-2025
Forma sugerida de citación: Fortes, M.; Soares, K.; Costa, F.; Menezes, C.; Colombini, A. (2025). “Metodología de
Reacondicionamiento de Edificios Hospitalarios”. Revista Técnica “energía”. No. 21, Issue II, Pp. 69-80
ISSN On-line: 2602-8492 - ISSN Impreso: 1390-5074
Doi: https://doi.org/10.37116/revistaenergia.v21.n2.2025.670
© 2025 Autores Esta publicación está bajo una licencia internacional Creative Commons Reconocimiento –
No Comercial 4.0 (https://creativecommons.org/licenses/by-nc/4.0/)
Retrofitting Methodology for Hospital Buildings
Metodología de Reacondicionamiento de Edificios Hospitalarios
M. Z. Fortes1
0000-0003-4040-8126
K. T. Soares1
0000-0002-2079-5176
F. O.T. Costa1
0000-0002-2928-003X
C. C. Menezes1
0000-0002-8906-4128
A. C. Colombini 1
0000-0002-8906-4128
1 Universidade Federal Fluminense - UFF, Programa de Pós-Graduação em Engenharia Elétrica e de Telecomunicações
(PPGEET), Niterói, Rio de Janeiro, Brasil
E-mail: mzamboti@id.uff.br, kerents@id.uff.br, fabricio_toscano@id.uff.br, carolinamenezes@id.uff.br,
accolombini@id.uff.br
Abstract
The building and construction sectors account for over
one-third of global final energy consumption and nearly
40% of total direct and indirect CO2 emissions. At the
same time, hospital buildings are often among the least
energy-efficient. Enhancing the energy performance of
existing hospital buildings through retrofitting measures
presents a significant opportunity for cost and energy
savings. However, hospitals have unique challenges,
such as continuous occupancy, heavy medical
equipment, and strict safety regulations. Additionally,
the lack of financial incentives and supportive policies
are among the biggest barriers to retrofitting hospital
facilities. This paper proposes an energy management
methodology for selecting the best retrofitting measures
for hospital buildings. Moreover, the study seeks to
define a priority ranking for the energy efficiency
measures selected in an energy retrofit project,
distinguishing between primary and supplementary
actions. The methodology includes a generic process
flow diagram, a systematic flowchart to facilitate
decision-making, and two tables outlining primary and
supplementary retrofitting measures.
Index terms— Energy Efficiency Actions, Energy
Management, Energy Retrofit, Hospital Buildings
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1. INTRODUCTION
Since the mid-20th century, dynamic changes such as
rapid urbanization and growth in production activities
have contributed significantly to global economic and
human development. However, the methods to achieve
this progress have come at a critical cost to the
environment [1]. By the early 1970s, human
consumption began to exceed the Earth's capacity for
regeneration [2]. It became clear that a modern lifestyle,
driven by current consumption patterns, is unsustainable,
leading to supply insecurity, high levels of waste, climate
change, pollution, and global warming [3].
Nevertheless, with the growth of the world
population, the contribution of buildings to global energy
consumption continues to increase, accounting for over
one-third of final energy use and more than 55% of global
electricity consumption [4]. The concern with the energy
consumption of buildings is worldwide and some
contributions to the theme are presented in [5-6].
Specifically in hospitals we have as examples the works
[7-8].
Following an increase of approximately 65% in
building floor area since 2000, energy demand from
buildings has surpassed that of other key sectors, such as
industry and transportation [3][9]. In this context,
without mandatory and effective policies, it is predicted
that approximately 70% of building floor area additions
will occur by 2050 [9]. Consequently, enhancing the
energy performance of existing buildings through retrofit
measures is crucial for the transition to sustainability.
In Brazil, current policies related to building retrofits
remain insufficiently robust. According to the Brazilian
Energy Research Office (EPE; in Portuguese, 'Empresa
de Pesquisa Energética'), one of the key historic
initiatives in the building sector is Law 10.295,
established in 2001, also known as the Energy Efficiency
Law. This law was formulated in response to the so-
called blackout crisis that affected approximately 800
Brazilian cities [10]. The Energy Efficiency Law
identified buildings as a priority area for promoting
energy efficiency mechanisms in Brazil, placing them
alongside other products that require energy assessment
and regulation. Consequently, the building sector became
part of one of the earliest initiatives addressing energy
efficiency in Brazil, the National Electricity
Conservation Programme (PROCEL; in Portuguese,
'Programa Nacional de Conservação de Energia
Elétrica'). The introduction of these policies had a
significant impact, with energy efficiency gains of
around 21% observed in residential buildings between
2005 and 2018 [10]. However, progress in implementing
retrofitting measures remains limited.
Consequently, the building retrofitting process
presents both challenges and opportunities [11].
Regarding opportunities, retrofit measures can provide
direct benefits, such as reduced heating and cooling costs,
as well as indirect benefits [12]. According to the World
Green Building Council [13], institutions that adopted a
green building approach reported a 23% increase in
productivity due to improved glare and brightness
control, a 5-14% improvement in test scores in schools
with optimal daylight, and a 10-25% improvement in
mental function and memory test performance among
workers exposed to outdoor views. Furthermore, research
indicates that bright sunlight in rooms led to a 22%
reduction in the need for pain medication, hospital stays
were reduced by 8.5%, and recovery rates were faster in
rooms with views of nature [13].
In this context, it is evident that, in addition to
improving energy efficiency, building retrofitting can
also offer opportunities to enhance human quality of life
by reducing exposure to external noise, improving
thermal comfort, and enhancing indoor air quality [14].
Therefore, there are significant potential benefits for
overall improvements in hospitals and healthcare
facilities through retrofitting, which is the primary focus
of this paper.
However, despite the numerous advantages of
retrofitting, the implementation rate for existing
buildings remains low. This low rate is due to several
challenges that hinder the retrofitting process, including
long payback periods, bureaucratic obstacles, lack of
awareness, insufficient data, uncertainties in the
decision-making process, and disruptions to ongoing
operations [15].
Concerning hospital buildings, additional challenges
must be considered. Hospitals house various services and
facilities that operate 24/7, including laboratories,
nurseries, restaurants, emergency rooms, recovery areas,
and surgical suites. Continuous occupancy, the presence
of heavy medical equipment, and strict safety regulations
further add to the complexity of these buildings [16].
Given the numerous challenges and opportunities, it
is evident that, although Brazil has various policies aimed
at improving energy efficiency in buildings, none provide
specific guidelines for retrofitting hospital buildings. In
general, there is no single standard that encompasses
energy management regulations tailored to the unique
requirements of hospital facilities. Furthermore, due to
the lack of knowledge dissemination on this subject and
the non-mandatory nature of existing energy efficiency
policies for buildings, identifying energy-saving
opportunities that account for both technical specifics
and financial constraints becomes highly challenging.
Motivated by these factors, this paper proposes a
retrofitting methodology for hospital buildings. The
methodology is designed to address these challenges by
providing a flowchart for selecting the most effective
actions for an energy retrofit project. This work aims to
clarify which actions should be prioritized within a range
of options, considering the constraints imposed by
available financial resources.
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The structure of the paper is as follows: Section Two
reviews related works, outlining the main barriers to
retrofitting hospitals and how various countries address
this issue. Section Three details the proposed retrofit
methodology, including guidelines for selecting the most
effective retrofit measures for hospitals based on
financial considerations and potential energy savings.
Finally, Section Four presents the conclusions and offers
suggestions for further research.
2. LITERATURE REVIEW
According to Papantoniou [17], hospital buildings are
often among the least energy-efficient public buildings in
many developed countries. Unlike residential and
commercial buildings, hospitals operate 24/7, serving
thousands of employees, patients, and visitors.
Additionally, stringent standards for ventilation, air
conditioning, lighting, and thermal comfort significantly
increase energy consumption. Shen [18] notes that the
energy consumption pattern of hospital buildings
exhibits both intermittent and continuous characteristics.
As a result, the energy load profile of hospitals varies
greatly, leading to substantial energy waste.
Bawaneh [19] indicates that, in U.S. hospitals, the
energy intensity is approximately 2.6 times higher than
that of other commercial buildings, ranging from 640.7
kWh/m² in the warmest regions to 781.1 kWh/m² in the
coldest areas.
This variability highlights how temperature
differences across geographical zones significantly
impact heating and cooling consumption. In contrast,
European hospitals have an average energy intensity of
333.4 kWh/m² [19]. The authors of [17] notes that
significant differences in hospital energy consumption
patterns arise not only from varying climatic zones but
also from factors such as the type of hospital (e.g.,
general, psychiatric, health center), the condition of the
building envelope, insulation levels, energy management
practices, and the age and maintenance of mechanical
equipment.
There isn´t recent data about electricity consumption
in hospital buildings in Brazil. According to Tolmasquim
[20], electricity consumption in large hospitals in Brazil
is divided as follows: 41% for air conditioning, 26% for
lighting, and approximately 5% for water heating.
Similarly, Bawaneh [19] reports that in U.S. healthcare
systems, major energy consumers include space heating
(29%), ventilation (12%), water heating (11%), and
cooling (11%). Other research indicates that Heating,
Ventilation, and Air Conditioning (HVAC) systems are
significant electricity consumers in hospitals worldwide,
accounting for 30-65% in India, approximately 51.36%
in Thailand, and 44% in the UK [19]. Generally, as noted
by Papantoniou [17], the largest electricity consumers in
hospitals are cooling machines, air compressors,
circulation pumps, HVAC fans, lighting, medical
equipment, and office equipment.
In light of this, Buonomano et al. [21] note that
hospitals have the highest energy consumption per unit
floor area in the building sector, making them prime
candidates for cost savings and energy-efficiency
measures through refurbishment. Consequently,
hospitals can allocate saved funds toward investing in
newer technologies to enhance patient care.
Radwan et al. [8] conducted a case study on a hospital
in Alexandria, Egypt, with a floor area of 31,019.2 m²,
focusing on implementing a retrofitting methodology due
to the continuous operation of medical devices and air
quality requirements in healthcare facilities. The study
evaluated energy savings by implementing various
retrofitting measures, including reducing lighting
intensity, adding wall insulation, and upgrading the
ventilation and air conditioning systems. Simulations
indicated that adopting a more modern air conditioning
system could potentially reduce the hospital's annual
energy consumption by approximately 34%. Radwan et
al. [8] concludes that the selected retrofitting measures
could yield over 41% electricity savings, equivalent to a
reduction of 7,068,178 kWh/year. The paper emphasizes
that hospitals are distinct from other commercial
buildings due to their specific airflow and ventilation
requirements.
Buzzi Ferraris [22] examined the Queensland
Children’s Hospital in Brisbane, Australia, as part of a
Deep Energy Retrofit (DER) project, defined by the IEA
EBC Program as a major renovation capable of reducing
site energy use intensity by 50%. The study found that
replacing fluorescent lighting with LEDs had a payback
time of approximately one year. The project also
included the installation of photovoltaic windows, which
have the potential to save 91 MWh per year with a
payback time of 14.2 years. Buzzi Ferraris [22] highlights
specific challenges of healthcare facilities, such as high
energy consumption due to medical equipment, 24/7
operation, the need for infection and temperature control,
and the inclusion of onsite kitchen and laundry services.
The study underscores that due to architectural design
constraints, not all retrofitting solutions available on the
market are optimal. Additionally, Buzzi Ferraris [22]
identifies financing as a major barrier in retrofitting
projects, as economic benefits are primarily assessed in
terms of energy savings, which often makes it
challenging for renovation projects to achieve the
expected cost-effectiveness.
The authors of [23] studied the implementation of
retrofit measures in three different healthcare facilities.
In Case Study 1, aimed at reducing energy costs in the
Cancer Center and the Emergency Department of a 40-
year-old acute-care facility, a new Heating, Ventilation,
and Air Conditioning (HVAC) system and LED lamps
were installed. Additionally, the building’s electrical
supply voltage was upgraded to a 12,000V system. In
[23] notes that the scope of energy efficiency measures
was limited due to the need to comply with healthcare
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facility standards for patient care areas. In Case Study 2,
the project involved renovating approximately 880 m² of
shell space in a hospital’s Radiology department and
constructing an Outpatient Clinic. The main criterion for
investing in energy-efficient equipment was a maximum
payback time of three years. Consequently, the hospital's
ventilation system was upgraded to a variable air volume
(VAV) system, a heat-recovery wheel system was
installed, and the lighting was upgraded. In Case Study
3, the project entailed the construction of a new 52-bed
Neonatal Intensive Care Unit on the hospital’s fourth
floor. At the time, the hospital's energy cost was
approximately 26 dollars per minute.
Hence, the analysis included several retrofitting
measures, such as upgrading the lighting system,
increasing the outdoor air ventilation rate to a minimum
of 30%, sourcing 59% of the total electricity demand
from renewable energy, and installing low-flow fixtures
for water-use reduction and carbon dioxide sensors to
improve outdoor air quality. In [23] emphasizes the
importance of ensuring that retrofitting projects for
existing hospitals are both energy-efficient and safe for
patients. Among the main patient safety concerns during
retrofit implementation in the case studies were noise,
vibration, dust, and asbestos. However, it is noted that
there are currently no standards or guidelines for
integrating patient safety with energy efficiency in
healthcare retrofit projects. Research conducted in
Aguascalientes, Mexico, proposed using Pinch
technology to reduce thermal energy consumption in the
hospital complex of the Instituto Mexicano del Seguro
Social. This study found that the measure could reduce
thermal power usage by 38% by adding four heat
exchangers to the system, which equates to a savings of
246,000 liters of diesel [17].
In Alonso [24], a comprehensive methodology was
proposed to enhance efficiency in multiple chiller plants
through targeted data analysis. This study involved data
aggregation, filtering, and projection operations to map
chillers and the entire electrical plant, enabling the
definition and adjustment of operational rules. The chiller
plant management software was implemented at the
Hospital de León in Spain to determine when to activate
or disable a chiller based on various efficiency criteria.
This implementation resulted in an electricity savings of
380,000 kWh over the studied year. However, the
approach did not guarantee optimal results, and iterative
applications of the methodology are required for
continued improvement.
Ardente [25] presented significant results from
implementing energy efficiency measures in various
public buildings. The study included installing solar and
wind power plants, upgrading the building envelope,
replacing lighting and glazing components, and
retrofitting HVAC installations. These measures yielded
substantial benefits. Out of an initial energy use of 19,590
GJ/year before the retrofit, an estimated 5,963 GJ/year of
energy savings was achieved after the retrofit of these
public buildings.
Billanes [26] presents two case studies that explore
the influential factors in implementing a 'Bright Green
Hospital' and the involvement of stakeholders in this
process. In the first case, efficiency actions included the
adoption of hospital policies for employees and
customers, an energy management program, a natural
lighting project for patient rooms, and the replacement of
old lighting with LEDs. The second hospital
implemented ISO-compliant energy management, set
standards for its air conditioning unit, installed LED
lighting, and incorporated large windows for natural
lighting. Additionally, Pinggoy Medical Center's power
management plan features photovoltaic solar panels and
a building management system (BMS).
Dainese [27] shared results from an investigation into
the energy-saving potential of a polyclinic building
within a hospital in the Netherlands. The analysis focused
on understanding the building’s characteristics and its
energy supply and demand. The findings led to
recommendations for energy-saving measures, such as
controlled ventilation and lighting rates. These measures
aimed to address discrepancies between the number of
people present and the building's full capacity, as well as
between the designed and installed values of lighting
systems. Additionally, the recommendations sought to
ensure that the air supply from the ventilation system is
adjusted according to occupancy levels rather than
remaining constant.
Additionally, Teke [28] presents several energy
conservation actions implemented in hospitals across
different countries between 2011 and 2020. Portugal was
noted for having the most comprehensive actions,
addressing various energy systems, including HVAC
systems, lighting, and other unspecified systems. The
research also details a series of energy efficiency actions
and their corresponding reductions in electricity
consumption. The actions are as follows:
• Application of advanced and integrated control
techniques to regulate HVAC and lighting systems.
Potential cost savings rate: 5 to 20% annually.
• Variable Speed Drive (VSD) installation for air
conditioning pumps and fans. Potential energy savings
rate: 50% (by reducing electric motor speed by 20%,
optimizing fan and pump run times).
• Integration of lighting control systems with low-
energy lighting. Potential energy savings rate: Up to
30%.
• Implementation of energy efficiency measures for
surgery rooms, focusing on reducing the air exchange
rate based on occupancy. Potential energy savings rate:
Up to 25%.
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• Layout changes of cooling equipment for rowless
servers in a hospital data center. Potential energy savings
rate: 30%.
• Continuous monitoring of energy systems.
Potential reduction in annual energy bills: 10 to 15%.
Ludin [29] examined the electricity use of a public
hospital in Malaysia, with a total consumption of
11,255,203.45 kWh/year. Proposed energy conservation
measures, including awareness campaigns, replacing
personal computers with laptops, and updating
refrigerators, could potentially reduce total electricity
consumption by approximately 429,743.39 kWh/year.
This would result in cost savings of RM 152,127.57/year
(or $36,510.62/year) and a decrease of 296,522.94
kg/year in CO2 emissions.
A second study focused on electricity load
distribution at another public hospital in Selangor,
Malaysia, where the annual electricity bill is about RM
8,599,122.56 (or $2,063,789.41). The energy audit
recommended additional measures, such as room
temperature control, an efficient lighting system, an
upgraded Air Conditioning Split Unit (ACSU), and the
installation of Variable Speed Drives (VSDs) to regulate
motor power. These measures are estimated to incur a
total cost of RM 748,606.65 ($179,665.59) with a
payback period of 1.78 years. The potential electricity
reduction is approximately 1,250,000 kWh/year,
resulting in savings of RM 421,706/year
($101,209.44/year) and a reduction of 869 tons of CO2
emissions annually.
It is evident that while the selected case studies
demonstrate potential energy savings and health benefits,
they also highlight specific challenges associated with
retrofitting healthcare facilities. These challenges include
obtaining financing, dealing with long payback periods,
selecting optimal solutions, ensuring compatibility of
new technologies with existing buildings, and addressing
a lack of standards and guidelines. Additional issues
involve meeting patient safety requirements, complying
with healthcare standards, and managing both internal
and external coordination.
In this context, Wang et al. [30] developed a
comprehensive list of obstacles to energy efficiency
within healthcare facilities in China. The study concludes
that government actions may have a more significant
impact on creating energy-efficient hospital buildings
than technical and economic barriers. The main
government-related obstacles include a lack of incentives
(such as subsidies, rewards, and special funds), the
absence of national and industry standards for energy
efficiency in healthcare facilities, and the lack of
enforceable and mandatory administrative requirements
from the government regarding the energy efficiency of
healthcare facilities.
3. PROPOSED RETROFIT STRATEGY
The literature review highlighted several challenges
related to retrofitting hospital buildings. In response to
these challenges, this section proposes a methodology to
guide the selection and implementation of retrofitting
measures. The proposed strategy includes:
• A generic process flow diagram outlining the five
main stages of a retrofitting project.
• An extensive systematic flowchart that details the
process flow, including decision-making steps.
• Two tables categorizing primary and
supplementary retrofitting measures.
These schematics form a comprehensive solution that
addresses primarily the financial, political, and
informational barriers associated with retrofitting
hospital buildings. Key differences between retrofit
guidelines for general buildings and those for hospitals
include the need for specialized training for employees
and users, adherence to stricter standards for hospital
electrical installations, and ensuring patient safety and
privacy, which require compliance with more stringent
regulations.
3.1 Generic Hospital Building Retrofit
Process
Five main stages have been identified as crucial for
overcoming barriers to retrofitting: energy diagnosis,
planning, technical and economic analysis,
implementation, and validation and verification. These
stages are illustrated in the process flow diagram shown
in Fig. 1.
Figure 1: The five key phases in a building retrofit project
Additionally, based on these five key stages, a
systematic approach has been developed, as depicted in
Fig. 2. This flowchart serves as a decision guide for
whether to proceed with or withdraw from the project.
The first stage, energy diagnosis, aims to assess the
building’s potential for energy savings. This stage
includes benchmarking, conducting energy audits, and
preparing a building performance report.
During benchmarking, the goal is to understand how
the building’s performance compares to similar
structures. This initial step provides baseline information
and helps identify opportunities for upgrades.
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Figure 2: Flowchart of the proposed methodology
Energy performance benchmarking provides
essential information for formulating energy
management plans and identifying opportunities for
performance upgrades [31]. According to [32], two
indicators are most commonly used internationally for
benchmarking in hospitals:
• Annual energy consumption per square meter of
the hospital’s building area;
• Annual energy consumption per inpatient bed in
the hospital
When adopting these indicators, it's crucial to
consider the hospital's specific characteristics and
operational aspects. For instance, outsourcing of services
such as food and laundry can reduce the hospital's direct
energy consumption, resulting in a lower baseline [33].
Therefore, regardless of the project's specific targets,
benchmarking is essential for establishing a baseline and
identifying the most effective actions. This is the first
step towards setting goals and conducting a more detailed
analysis of the building through an energy audit.
An energy audit is a fundamental component of any
retrofitting project, involving the analysis of energy data
and user profiles. It provides a systematic assessment of
areas where energy is wasted, how energy is utilized, and
where improvements can be made [11]. Given the
complexity of hospital facilities, including their use of
specialized medical devices and stringent safety
requirements, conducting energy audits can be
particularly challenging. Therefore, it is advisable to
engage a specialist auditor if possible [31].
Finally, after conducting benchmarks and energy
audits, an energy performance report must be developed
to determine whether the building has energy-saving
potential to proceed to the next stage. If the building has
no energy-saving potential, the energy diagnosis should
be revisited in one year, as depicted in Fig. 2.
Tracking consumption by cost centers through a
demand manager is essential to better understand energy
systems, define areas of interest, and evaluate
opportunities for action without delay. In this regard,
both energy losses and usage profiles are necessary
variables for evaluating a building’s systems [31].
Generally, some critical questions must be answered to
continue an energy efficiency program:
• How much energy is being consumed?
• Who is consuming energy?
• How is energy being consumed, and how efficient
are the building systems?
In the second stage, the focus shifts from diagnosing
the problem to planning the solution. This stage is
referred to as the planning stage. In this step, both
qualitative goals and quantitative targets must be defined.
According to [31], many hospitals establish both short-
and long-term goals. By setting short-term goals,
immediate cost savings can accumulate over time, which
may help fund longer-term upgrades. Defining these
goals is also beneficial when assessing energy audit data.
At this stage, a more in-depth assessment and
diagnosis of the building’s performance are considered
decisive factors. Here, performance assessment is crucial
for evaluating the life cycle environmental and economic
factors that will determine whether it is better to retrofit
the building or demolish and rebuild it, as depicted in Fig.
2. Since retrofit options typically have lower life-cycle
economic costs than rebuilding, the latter option might be
considered only in critical situations [34].
Once the decision is made to proceed with the retrofit,
it is important to establish a well-defined scope to ensure
the project plan is functional. This step includes defining
the baseline, indicators, and assessment tools to be
evaluated during and after the retrofit. Additionally, it
involves selecting the retrofit level, which can be
categorized as economical, standard, or sophisticated.
In this regard, the flowchart presented in Fig. 3
illustrates the "Retrofit Action Plan Selection" step
within the planning stage. Specifically, the "Selection of
Retrofit Actions" sub-flowchart is part of the "Project
Schedule," a crucial phase in the proposed methodology
flowchart. This excerpt aims to guide the selection of a
retrofit plan that aligns with financial constraints. To
select a feasible plan, it is essential to define the project’s
spending limits, taking into account available financing
and partnership options. Establishing the retrofit level
based on financial considerations helps narrow down the
possible retrofit measures, making the decision process
more straightforward.
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In low-budget scenarios, the project is typically
limited to an economical retrofit, which may include only
operation and maintenance measures (O&M) or minimal
emergency actions. If the budget permits more than just
O&M actions, the project may reach a standard level,
incorporating more advanced measures. In cases where
there are numerous retrofit opportunities and substantial
capital available, a sophisticated retrofit project may be
considered, potentially including measures such as
installing photovoltaic systems and cogeneration
technologies.
The planning stage concludes with the selection of
retrofit measures and the development of a project
schedule. This timetable outlines the deadlines and
milestones that must be met to ensure timely project
completion. Given that the project schedule is dependent
on the chosen retrofit measures, a detailed and
comprehensive guide is essential for making these
decisions, as elaborated in the following section.
Figure 3: Decision on the level of retrofitting
It is important to note that the complexity of
retrofitting actions extends beyond their selection.
Implementing these actions presents additional
challenges, particularly for hospitals and other healthcare
facilities. Many of these challenges can be anticipated
during the planning stage. Healthcare buildings have
unique characteristics, such as continuous operation,
patient security requirements, and stringent sterilization
and cleaning protocols [35].
To ensure the well-being of patients and staff,
retrofitting hospitals must minimize impacts on their
daily operations and maintain the constant functionality
of critical hospital systems. It is crucial to evaluate
equipment usage in building controls beforehand.
According to [36], hospitals need careful zoning to
provide isolation and create negatively pressurized
spaces to minimize the risk of infection transmission.
Therefore, the retrofit project must account for
scheduling measures such as dust control, patient
relocation, and the use of negatively pressurized
anterooms. Additionally, coordinating the retrofit
schedule with the nursing and hospital management
teams is essential to align the hospital's operations with
the retrofit implementation.
Additionally, it is crucial to ensure that anyone
working on-site during the retrofitting project, especially
in inpatient rooms or other sensitive areas, is healthy and
meets all medical requirements for working in such
environments. Therefore, careful planning must include
reviewing hospital codes, verifying health and safety
regulations, and scheduling interruptions to hospital
operations to facilitate the implementation of retrofitting
measures [35].
The third stage involves the technical and economic
analysis of the selected retrofit plan. During this phase,
various analyses and studies are conducted to prepare for
the implementation of the chosen measures. This
includes performing energy performance simulations,
quantifying potential energy savings, detailing the
project description and specifications, examining budget
expenditures and cash flow, and assessing performance
and investment risks.
In this regard, the economic and risk analyses are
crucial for deciding whether to proceed with the retrofit
project or withdraw. Economically, several methods can
assess the feasibility of each retrofit measure, including
net present value (NPV), internal rate of return (IRR),
benefit-cost ratio (BCR), and payback time. Risk analysis
is equally important, as hospital retrofitting involves
numerous uncertainties. This analysis provides decision-
makers with the confidence needed to select and
implement the most appropriate retrofit solutions. Key
uncertainties include the estimation of savings, energy
use measurements, weather forecasts, changes in
consumption patterns, and system performance
degradation. These factors must be evaluated to ensure
that the chosen solution is the most viable option. Thus,
to proceed to the implementation stage, the analysis must
demonstrate the best cost-benefit alternative.
The fourth stage involves the on-site implementation
of the selected retrofit measures. During this phase,
testing and commissioning are conducted to ensure that
the building achieves optimal energy efficiency.
Following the implementation and adjustment of retrofit
measures, measurement and verification (M&V)
methods must be employed to monitor the performance
of the energy systems [37]. This stage also includes a
post-occupation survey to assess occupant and owner
satisfaction with the retrofit's overall results.
Additionally, the outcomes of the retrofit and the
operation and maintenance (O&M) methods are
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documented in a report. This report should detail the
building’s efficiency parameters and evaluate potential
areas for further improvement.
3.2 Retrofit Measures for Hospital
Buildings
Assuming that each main efficiency action affects
subsequent actions, this section emphasizes the
importance of following a systematic criterion when
selecting retrofitting measures for a building. According
to [31], the staged upgrade approach seeks to enhance
building systems by adhering to a specific order, where
improvements in one system influence others. For
instance, upgrading lighting systems first can alter the
thermal load, which in turn impacts the design of the
cooling systems. Similarly, a reduction in energy
consumption due to improved lighting can also affect the
performance and sizing of the building’s photovoltaic
system.
In light of this, the paper proposes a methodology for
selecting the appropriate retrofit plan. Two distinct tables
of important retrofitting measures have been developed
to differentiate between actions that directly reduce
energy consumption (primary measures) and those that
rely on the building’s consumption history
(supplementary measures). Each table prioritizes the
actions to ensure that each upgrade measure considers
how changes will impact subsequent actions.
The rationale for distinguishing between these two
lists is to prevent over-dimensioning of power generation
systems, avoid unnecessary investments, and prioritize
immediate actions that reduce electricity costs. As
financial factors are a significant barrier in retrofitting
projects [30], the methodology aims to minimize related
expenses by avoiding unconstrained actions. By adhering
to the defined priorities, it is anticipated that the building
will achieve maximum energy savings.
The retrofitting actions illustrated in the primary and
supplementary measures include auxiliary loads,
lighting, HVAC systems, flow pumping systems, water
heating, power generation systems, data analysis of
electricity bills, and power quality. The criterion for
selecting these actions involved a technical analysis of
the appliances and components, along with an evaluation
of the most energy-efficient systems available on the
market. This approach aims to simplify the O&M stage
by leveraging predictive, preventive, and corrective
maintenance activities [31].
The following subsections will illustrate the impact of
these measures. It is important to note that technological
advancements over recent decades have led to diverse
options for reducing electricity consumption and
retrofitting measures. For instance, replacing
incandescent luminaires with LED lamps can now
include advanced features such as presence detection
systems [36].
Additionally, as identified during the literature
review, one of the factors that complicate the success of
retrofitting projects is the difficulty in decision-making
and the inadequate selection of retrofit actions [30]. As
discussed in Section 3, determining a retrofit level based
on economic aspects helps narrow down the possible
retrofit actions. However, in addition to financial
considerations, the selection of retrofit measures should
also account for technical aspects [21]. In this context,
the flowchart presented in Fig. 4 illustrates the process
for prioritizing and selecting primary and supplementary
measures during the project schedule
Figure 4: Selection of retrofitting measures
The process begins with a broad selection of
retrofitting measures based on economic considerations.
It then progresses through a pipeline that refines the
options according to the building’s characteristics.
Initially, it is assessed whether the building has already
implemented any supplementary actions, such as
photovoltaic generation. If so, primary retrofit actions
should be prioritized to ensure optimal performance of
the building systems. This reduction in consumption
might necessitate rescaling systems before proceeding
with the selected measures.
Conversely, if the building has not yet implemented
any supplementary measures, it is essential to determine
whether such measures are needed. If so, primary actions
must be implemented first. Subsequently, when
technically and economically analyzing the
supplementary measures, it is crucial to consider that the
primary measures will have been completed beforehand.
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Fortes et al./ Metodología de Reacondicionamiento de Edificios Hospitalarios
3.2.1 Primary Retrofit Measures
From sources such as [31], [32], and [36], it is evident
that numerous efficiency measures can be implemented
in a hospital retrofitting project. Consequently, this
preliminary work has selected the most relevant
measures for hospital energy systems, encompassing
both end-use and generation profiles. Fig. 5 presents
various individual retrofitting measures specifically
aimed at reducing energy consumption in hospitals.
Figure 5: Primary Measures
Some of these measures may impact multiple energy
systems within a hospital. Thus, the developed table
facilitates visualization of the potential for simultaneous
implementation of several immediate retrofitting
measures.
These measures are directly related to the
implementation of energy-efficient technologies. It is
important to recognize that energy efficiency aims to
delay the need for new energy developments by
preserving the environment and altering the electricity
consumption patterns of individuals and institutions.
Additionally, it seeks to advance technology, introduce
energy-efficient appliances to the market, and promote
rational energy use. In this context, careful project
planning is crucial to achieving successful energy
efficiency and ensuring lasting results.
It is prudent to reduce the loads of medical and office
equipment, as well as laundry and kitchen appliances,
before making HVAC systems more efficient or
implementing other advanced measures. A
straightforward approach to reducing these loads is to
replace such devices with high-efficiency equivalents.
This illustrates how adhering to a prioritized order for
implementing retrofitting actions can significantly
contribute to the project's success.
3.2.2 Supplementary Retrofit Measures
After implementing the efficiency measures that
minimize energy waste the most, you can proceed with
retrofitting actions that depend critically on the
building’s electricity consumption history. Fig. 6
summarizes some of these measures.
Similar to Fig. 5, Fig. 6 relates efficiency measures
specified on the vertical axis with the opportunity zones
for energy efficiency, set on the horizontal axis, that are
impacted by these measures.
Figure 6: SupplementaryMeasures
4. CONCLUSIONS
This paper addresses the critical issue of energy
efficiency in hospital facilities and presents a systematic
methodology for retrofitting hospital buildings. Based on
the development of the proposed methodology and the
literature review, the following findings are highlighted:
1. Retrofitting Existing Buildings: It is essential for
advancing sustainability and achieving long-term energy
savings.
2. Energy Efficiency in Hospitals: Hospitals are
among the least energy-efficient buildings, thus offering
significant potential for energy savings.
3. Specialized Technical Team: Effective
coordination of an Energy Saving Plan within a hospital
requires the formation of a specialized technical team.
4. Training and Support: It is crucial to prepare and
provide teams to train employees and users on
maintaining and enhancing the results achieved through
energy efficiency measures.
5. Job Creation: Investments in energy efficiency
can drive job creation, particularly when high energy
efficiency potentials are identified.
6. Challenges in Implementation: Despite its
advantages, retrofitting implementation remains low due
to economic, political, and informational barriers.
Hospitals face additional challenges, including
continuous occupancy, complex medical equipment, and
patient safety requirements.
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Edición No. 21, Issue II, Enero 2025
7. Strengthening Policies: There is a clear need to
reinforce energy efficiency (EE) policies for buildings to
make them compulsory.
8. Decisive Moments: Three critical stages before
implementing a retrofit project include energy diagnosis,
planning, and performance and risk analysis.
9. Uncertainty and Methodology: Due to the high
level of uncertainty associated with building retrofitting
investments, developing methodologies that facilitate
more straightforward decision-making is essential.
These findings were crucial in developing a
comprehensive strategy to make hospital retrofitting
feasible. The methodology primarily addresses financial,
political, and informational barriers. Key goals include
simplifying the decision-making process and reducing
retrofitting expenses by avoiding unconstrained actions.
To achieve these objectives, the methodology proposes
classifying measures into primary and supplementary
categories and adopting a staged retrofit strategy.
By systematically evaluating each obstacle, the
approach aims to streamline the retrofitting process,
ensuring that actions are both cost-effective and
impactful. The classification helps prioritize immediate
measures that directly reduce energy consumption, while
the staged strategy ensures a logical progression of
retrofitting actions based on their impact and feasibility.
Considering that each upgrade measure affects
subsequent retrofitting actions, the proposed strategy
distinguishes between two types of retrofit measures:
primary and supplementary. This approach helps prevent
over-dimensioning of energy generation systems, avoids
unnecessary investments, and prioritizes immediate
actions to reduce electricity costs.
In conclusion, this paper initiates an important
discussion on retrofitting hospital buildings and
highlights study and policy gaps that impede such
projects. For future research, it is recommended to
conduct extensive studies on operational issues in
hospital retrofitting and to perform regional analyses of
current retrofitting codes.
REFERENCES
[1] Fotiou, S. et al.: Sustainable Consumption and
Production: A Handbook for Policy Makers, 2015.
[2] Venetoulis, J., and Talberth, J. “Refining the
ecological footprint.” Environment, Development
and Sustainability 10, (2007):441-469.
doi:10.1007/s10668-006-9074-z. doi:
10.1007/s10668-006-9074-z.
[3] Pèrez-Lombard, L., Ortiz, J, and Pout,C. “A review
on buildings energy consumption information.”
Energy and Buildings 40, No.3 (2008): 394-398.
doi:10.1016/j.enbuild.2007.03.007.
[4] Abergel, T. et al.: Towards a zero-emission, efficient,
and resilient buildings and construction sector:
Global Status Report 2017. UN Environment and
International Energy Agency: Paris, France, 2017.
[5] Alsaadani, S., Hamza, M., and Fahmy, M.
“Reconciling retrofitting with IEQ to maintain
energy, environmental and economic performance:
A methodological approach for generic office
buildings.” Building and Environment 264, No.1
(2024). doi: 10.1016/j.buildenv.2024.111868.
[6] Weerasinghe, L.N.K., Darko, A., Chan, A.P.C., Blay,
K.B., and Edwards, D.J. “Measures, benefits, and
challenges to retrofitting existing buildings to net
zero carbon: A comprehensive review.” Journal of
Building Engineering 94, No.1 (2024).
doi:1010.16/j.jobe.2024.109998.
[7] Shi, Y., and Chen, P. “Energy retrofitting of hospital
buildings considering climate change: An approach
integrating automated machine learning with
NSGA-III for multi-objective optimization.” Energy
and Buildings 319, No.1 (2024).
doi:10.1016/j.enbuild.2024.114571.
[8] Radwan, A.F., Hanafy, A.A., Elhelw, M., and El-
Sayed, A.A. “Retrofitting of existing buildings to
achieve better energy-efficiency in commercial
building case study: Hospital in Egypt.” Alexandria
Engineering Journal 55, No.4 (2016):3061-3071.
doi:10.1016/j.aej.2016.08.005.
[9] International Energy Agency – IEA: Perspective from
the clean energy transition. The critical role of
buildings, 2019.
[10] Empresa de Pesquisa Energética – EPE: Ações para
Promoção da Eficiência Energética nas Edificações
Brasileiras: no caminho da Transição Energética,
2020. (in portuguese)
[11] Ma, Z., Cooper, P., Daly, D., and Ledo, L. “Existing
building retrofits: Methodology and state-of-the-
art.” Energy and Buildings 55, (2012):889-902. doi:
10.1016/j.enbuild.2012.08.018.
[12] Liu, Y., Liu, T., Ye, S., and Liu, Y. “Cost-benefit
analysis for Energy Efficiency Retrofit of existing
buildings: A case study in China.” Journal of Cleaner
Production 177, (2018):493-506.
doi:10.1016/j.jclepro.2017.12.225.
[13] World Green Building Council: The business case
for green building: a review of the costs and benefits
for developers, investors and occupants.
Washington, DC, 2013.
[14] Bosh, F.P., Cervera, C., and Ysa,T. “Key aspects of
building retrofitting: Strategizing sustainable cities.”
Journal of Environmental Management 248,
15(2019). doi: 10.1016/j.jenvman.2019.07.018.
78
Fortes et al./ Metodología de Reacondicionamiento de Edificios Hospitalarios
[15] Regnier, C., Sun, K., Hong, T., and Piette, M.A.
“Quantifying the benefits of a building retrofit using
an integrated system approach: A case study.”
Energy and Buildings 159, (2018): 332-345. doi:
10.1016/j.enbuild.2017.10.090.
[16] Gaspari, J., Fabbri, K., and Gabrielli, L. “A study on
parametric design application to hospital retrofitting
for improving energy savings and comfort
conditions.” Buildings 9: No.10 (2019). doi:
10.3390/buildings9100220.
[17] Kolokotsa, D., Tsoutsos, T., and Papantoniou, S.
“Energy conservation techniques for hospital
buildings.” Advances in Building Energy Research,
6, No.1 (2012). doi:
10.1080/17512549.2012.672007.
[18] Shen, C., Zhao, K., Ge, J., and Zhou, Q. “Analysis
of building energy consumption in a hospital in the
hot summer and cold winter area.” Energy Procedia
158, (2019): 3735-3740.
doi:10.1016/j.egypro.2019.01.883.
[19] Bawaneh, K. et al., “Energy Consumption Analysis
and Characterization of Healthcare Facilities in the
United States.” Energies 12, No.19 (2019). doi:
10.3390/en12193775.
[20] Szklo, A.S., Soares, J.B., and Tolmasquim, M.T.
“Energy consumption indicators and CHP technical
potential in the Brazilian hospital sector.” Energy
Conversion and Management 45, No.13-14
(2004):2075-2091. doi:
10.1016/j.enconman.2003.10.019.
[21] Buonomano, A., Calise, F., Feruzzi, G., and
Palombo, A. “Dynamic energy performance
analysis: Case study for energy efficiency retrofits of
hospital buildings.” Energy 78, (2014): 555-572.
doi:10.1016/j.energy.2014.10.042.
[22] Buzzi Ferraris, A. Retrofit techniques for public
buildings to improve energy efficiency and reduce
management costs. Case study: children's hospital in
Brisbane. Italy,2019. Tesis.
[23] Mohammadpour, A., Anumba, C.J., and Messner,
J.I. “Retrofitting of Healthcare Facilities: Case Study
Approach.” Journal of Architectural Engineering 23,
No.3(2017). doi: 10.1061/(ASCE)AE.1943-
5568.0000248.
[24] Alonso, S. et al. “A data-driven approach for
enhancing the efficiency in chiller plants: A hospital
case study.” Energies 12. No.5(2019). doi:
10.3390/en12050827.
[25] Ardente, F. et al. “Energy and environmental
benefits in public buildings as a result of retrofit
actions.” Renewable and Sustainable Energy
Reviewsg 15, No.1 (2011): 460-470.
doi:10.1016/j.rser.2010.09.022.
[26] Billanes, J. Y., Ma, Z. and Jorgensen, B.N. “The
bright green hospitals case studies of hospitals'
energy efficiency and flexibility in Philippines.” In
8th International Conference on Power and Energy
Systems (ICPES) – IEEE, 2018. doi:
10.1109/ICPESYS.2018.8626916.
[27] Dainese, E., Walker, S., Maassen, W., and Zeiler,
W. “Towards zero energy hospital buildings: a
polyclinic building as case study.” E3S Web of
Conferences 11, (2019). doi:
10.1051/e3sconf/201911104021.
[28] Teke, A. “Overview of energy savings and
efficiency strategies at the hospitals.” International
Journal of Economics and Management
Engineering, (2014).
[29] Ludin, N. A. et al. “Energy efficiency action plan
for a public hospital in Malaysia. Alam Cipta.” Alam
Cipta 12, SI 1 (2019).
[30] Wang, T., et al. “Building energy efficiency for
public hospitals and healthcare facilities in China:
Barriers and drivers.” Energy 103, (2016):588-597.
doi: 10.1016/j.energy.2016.03.039.
[31] NREL: Advanced Energy Retrofit Guide: Practical
Ways to Improve Energy Performance; Healthcare
Facilities. National Renewable Energy Laboratory
(NREL), 2013.
[32] Bureau of Energy Efficiency – BEE: Energy
Efficiency in Hospitals: Best Practice Guide, 2009.
[33] Moschuris, J.S. and Kondylis, M.N. “Outsourcing in
public hospitals: a Greek perspective. Journal of
Health Organization and Management.” Journal of
Health Organization and Management 20, No.1
(2006):4-14. doi: 10.1108/14777260610656534.
[34] Dong, B., Kennedy, C., and Pressnail, K.
“Comparing life cycle implications of building
retrofit and replacement options.” Canadian Journal
of Civil Engineering 32, No.6 (2005). doi:
10.1139/l05-061.
[35] Fairbanks, P. “Hospital Energy Use: Taking
Advantage of Energy Efficiency.” Electric Energy
T&D Magazine, No.4 (2018).
[36] Natural Resources Canada – NRC: Major Energy
Retrofit Guidelines for Commercial and Institutional
Buildings: Hospitals. 2018.
[37] Efficiency Valuation Organization – EVO:
Protocolo Internacional de Medição e Verificação de
Performance - Conceitos e Opções para a
Determinação de Economias de Energia e de Água
Volume 1, 2012. (in portuguese)
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Marcio Zamboti Fortes- Nació en
Volta Redonda, Brasil en 1969.
Recibió su título de Ingeniero
Eléctrico de la Escola de
Engenharia de Vassouras en 1991;
de Master en Ingeniería Energética
de la Universidade Federal de
Itajuba en 2000; y su título de
Doctor en Ingeniería Eléctra de la Universidade de São
Paulo. Sus campos de investigación están relacionados
con Eficiencia energética, calidad energética, fuentes
renovables y gestión/mantenimiento de sistemas
industriales.
Keren Tenorio Soares- Nació en la
ciudad de Petrópolis, Brasil en
1991. Recibió su título de
Ingeniero Eléctrico de la
Universidade Federal Fluminense
en 2015; de Master en Ingeniería
Eléctrica de la Universidade
Federal Fluminense, en la ciudad de
Niterói, Brasil en 2022. Sus campos de investigación
están relacionados con Modelado y Análisis de Sistemas
de Energía Eléctrica, con área de concentración de
Sistemas de Energía Eléctrica y énfasis en Eficiencia
Energética.
Fabrício Oliveira Toscano da
Costa - nació el 26 de julio de 1994
en Río de Janeiro, Brasil. Es
Técnico en Electrónica, titulado por
FAETEC - Escola Técnica
Estadual Visconde de Mauá, y
posee una Licenciatura en
Ingeniería Eléctrica por la
Universidade do Estado de Río de Janeiro (UERJ).
Recibió su título de Master in Ingenieria Eléctrica de la
Universidade Federal Fluminense, en 2024. Sus áreas de
especialización incluyen energías renovables, eficiencia
operativa y gestión de sistemas fotovoltaicos
Caroline Cunha Menezes - Nació
en Brasil en 1994. Obtuvo su título
de Ingeniera Eléctrica en la
Universidade Federal Fluminense
en 2019. Realizó parte de sus
estudios en la Queen Mary
University of London. Completó su
maestría en la Universidade
Federal Fluminense, donde su campo de investigación se
centró en la digitalización de los sistemas eléctricos.
Angelo Cesar Colombini - Nació
en Casa Branca, São Paulo en 1965.
Recibió el título de Ingeniero
Eléctrico en 1990; de Máster en
Ingeniería Eléctrica por la
Universidade de São Paulo en 1994;
y su título de doctor también por la
Universidade de São Paulo, Brasil.
Su área de investigación está relacionada con la
Ingeniería de Sistemas Computacionales, Big Data y
Machine Learning.
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