Resumen | In the last two decades the number of small breweries and microbreweries has grown dramatically, representing
more than 90% of all breweries in several countries. The brewing process requires heat, cold, and mechanical
power, ...
In the last two decades the number of small breweries and microbreweries has grown dramatically, representing
more than 90% of all breweries in several countries. The brewing process requires heat, cold, and mechanical
power, which are mainly provided by gas and electricity. The integration of solar energy to achieve
decarbonization in the industry is still incipient. The literature reveals that most studies in this regard are made
for medium and large breweries. Likewise, the few cases of solar thermal and photovoltaic integration have
been in larger breweries. Therefore, the premise of this thesis is that solar energy integration can also be
profitable for small-scale industries under the current market conditions.
Initially, in the present thesis an economic prefeasibility study of solar thermal and photovoltaic integration for
a microbrewery was carried out for Chile and Spain. Both countries with present high solar resources and differ
from each other in the cost of conventional energy (fuels and electricity). The photovoltaic system was profitable
for both countries under certain price and solar radiation conditions. The solar thermal system was profitable
for Chile in most regions. However, in Spain it was not profitable without subsidies since the price of gas in
Spain is much lower than in Chile.
For these reasons, it was of interest to know in detail the consumption of a microbrewery to conduct a more
detailed study of the use of photovoltaic energy. Thus, a monitoring campaign was carried out to characterize
the consumption profile of a microbrewery located in southern Spain. It has been identified that the specific
energy consumption per liter of beer may be five times that of a large brewery. In addition, the small-scale
components for supplying cold usually operate off-design conditions, and there is no literature information
regarding the performance under these conditions. Therefore, during the measurement campaign, data has been
collected to adjust the performance curves of these components.
Additionally, a simulation tool has been created in TRNSYS that includes the adjusted models of the
components. It has been contrasted with measurement data and electricity consumption bills, resulting in a
good agreement. The tool may be modified to be used for microbreweries of different sizes or with a different
consumption profile. In addition, it can be used for other types of small industries that require cold, heat, and
other electrical consumption.
The results of the techno-economic analysis carried out in Spain reveal that in any situation a photovoltaic
system would be profitable. The cost of energy could be reduced by up to 46.6% for the best solar radiation
conditions and market prices. However, in a more moderate scenario where the size of the system is also limited
by regulation, the reduction in the cost of energy can vary between 6.7% and 31.5%, for regions with low and
high solar radiation respectively. Additionally, the payback periods are between 3.2 and 19.2 years, depending
on the level of solar radiation, conventional energy prices, and the size of the PV system.
Finally, the contribution of this study to the state of the art begins with the identification of gaps in the literature
regarding energy use in small industries. In addition, the on-site monitoring campaign, together with the
subsequent adjustment of performance curves, allows identifying the consumption in real conditions for this
type of industries. On the other hand, the creation of a simulation tool whose development is explained in detail
will allow it to be used and/or adapted for other industries, increasing its potential use. Finally, the economic
results seek to demystify the belief that solar energy is expensive and that can only be used in large industries
to be profitable. The aim is to move towards decarbonization, in order to meet the objectives of international
initiatives against climate change.
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