B UILDING & M ANAGEMENT
E LECTRICITY IN HOSPITALS : SOLUTIONS BASED ON ECONOMIES OF SCALE
V OLUME 3 I SSUE 3 S EPTEMBER - D ECEMBER 2019 G. S ÁNCHEZ -B ARROSO , M. G ÓMEZ -C HAPARRO , M. J. C ARRETERO -A YUSO AND J. G ARCÍA -S ANZ -C ALCEDO (2019). B UILDING & M ANAGEMENT , 3(3): 12-16
be met with renewable energy sources, the generation of
electricity from fossil fuels still prevails. For this reason, the
policy strategies of developed countries aim to reduce the
environmental impact of energy production [5].
consumption is key to reducing transport losses and,
consequently, minimising transport taxes. Although this style of
decentralized management would greatly benefit large
consumers [15], there are a number of technical, economic,
regulatory and environmental obstacles that prevent it [16].
According to the objectives of the Building Energy Efficiency
Directive (2012/27/EU), 2020 is established as the deadline
for the implementation of the so-called Nearly Zero Energy
Buildings (nZEB). Newly constructed buildings in public
ownership, including hospitals and health centres, must have
almost zero energy consumption after 31 December 2018 [6].
However, energy thresholds have not been defined
specifically for hospitals [7]. Hospital management through
Healthcare Engineering is focused on energy and
environmental efficiency and therefore becomes an effective
tool in this regard [8].
Ferreira Silva, Kopp and da Costa Guida [17] evaluated the
aspects related to the evolution towards the integration of
photovoltaic solar energy in Brazil's centralized generation
system, in view of the country's potential in terms of
irradiation. They highlighted the role of R&D and the benefits
derived from favorable energy policies to ensure their
integration.
García Sanz-Calcedo et al. [18] carried out an analysis of the
annual electricity consumption of 13 Spanish hospitals between
2008 and 2017 with the aim of determining consumption
indicators based on the hospital activity carried out in each
hospital. The results showed a high correlation between
average annual energy consumption and the annual number
of discharges, number of emergency actions and number of
hospital stays.
In Spain, since energy consumption is recorded as ktoe,
electricity consumption correlated with gross domestic product
(GDP) until 2014. Since that year, GDP has grown by 13%
and electricity consumption by 4.6% [9]. Nowadays, GDP and
electricity consumption do not maintain the same proportion of
growth. It can therefore be concluded that consumers have
opted for energy saving and efficiency measures [10].
Analyses of historical consumption are a useful tool for
optimising energy expenditure in the future; however, tools
based on fuzzy logic are being developed to seek the lowest
cost of purchasing energy in the electricity market taking into
account all the regulatory conditions that govern it [19].
Annual electricity demand in Spain has increased by 10 TWh
from 2014 to 2018, representing an increase of 4.12%.
However, the installed capacity of renewable energy
maintains their contribution of around 50% of the net
generation structure since 2014 [11]. A building that requires
a 1-36 kV supply with a contracted power greater than 450
kW is considered a large consumer in the electric power
context. Large Spanish consumers demand 12% (~30 TWh) of
the total [12].
The aim of this work is to analyse the different options for
contracting electricity supplies for large consumers, such as
hospitals, so that they offer the greatest savings in energy
costs. This work will be useful for hospital managers, opening
up the possibility of analysing little-known electricity supply
options.
Analysing the general energy consumption of a building
allows managers to have useful information for making
decisions regarding the contracting of supply services, and to
study the options of electrical contracting in particular. This is
the reason why it is useful to make this audit effort.
2. M ETHODOLOGY
A compilation and study were carried out of the technical-
economic conditions required by each of the contracting
options offered by distribution companies to large consumers,
such as hospitals, in Spain, and their implications for hospital
management.
García Sanz-Calcedo [13] analysed and quantified the
energy performance of 55 health centres in Extremadura
(Spain) in order to estimate the possibilities of savings through
the use of specific measures to reduce their energy demand.
The average annual consumption was 86.01 kWh/m2, with a
standard deviation of 16.8 kWh/m2. The results show that a
potential annual saving of 4.77 €/m2 can be achieved.
The study of supply contract options took into account the
existence of associated risks. The risk can be classified into
two types according to its relationship with the consumer
himself or with the electricity market.
Bakaimis y Papanikolaou [14] estimated a 45% reduction in
the electricity consumption of a hospital in Greece resulting
from the implementation of energy policies and proposing an
investment in photovoltaic panels and the change from current
lighting technology to LEDs.
On the consumer side, the risk is related to energy demand
and the accuracy of forecasts. The energy demand of a
building defines its consumption profile, but it is influenced by
seasonality (monthly, seasonal, etc.), which opens the door to
uninterruptibility as a mechanism for active demand
management. The accuracy of the forecasts minimizes the
penalty that a deviation in forecasts implies, either because
they force a consumer to go to the electricity market to
purchase the energy or because surpluses are produced after
The installation of renewable energy sources in large hospitals
should broaden their share of the energy mix by favouring
distributed generation. The proximity between generation and
13