3 Installations of Solar Systems in Remote Areas …
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A metal hydride based pumping system, wherein, a metal hydride is heated using
solar energy which produces a Hydrogen gas. It then pressurizes a piston which
ultimately produces a water-head up to 15 m on Sunny days (Wazed et al. 2018).
The solar thermal based pumping systems exhibited an efficiency of about 3%
in comparison to 6% of that of Photovoltaic systems. But efficiency shall not be
the prime concern in case the systems working on renewable sources. For remotely
located society irrigation purposes, a locally evolved solar thermal based irrigation
system is reported to be more cost effective and ecofriendly as compared to PV
technology (Wazed et al. 2018).
Electricity generation through solar based Micro-grid: The lowest ever rural
electricity tariff in the world is at Myanmar. Xu et al. (2019) have provided an
economic comparison of various microgrid systems e.g., Solar PV based microgrid,
diesel based microgrid, biogas based microgrid, solar PV cum diesel based microgrid,
and solar PV cum biogas based microgrid. In their study, rice husk is used as a source
for biogas energized micro-grid. Among these five types of microgrids, solar PV
based microgird generated an excess electricity of about 30% more than the local
requirements. It is attributed to the hourly variation of the incoming solar radiation
(Xu et al. 2019).
Energy Generation from Biogas: Energy can also be obtained from biogas, which
can be produced using household waste products. The disadvantage of having lesser
energy production efficiency can be improved by uniting it with a solar power. This
technology is termed as solar assisted biogas power generation unit. Biogas is generally produced from biodegradation of organic wastes/resources, by bacteria under
anaerobic condition. Such biogas generation units can be installed anywhere either
in urban area or in remotely located hilly rural area. It comprises Methane with some
amount of Carbon Dioxide, and little proportion of Hydrogen Sulphide. Based on a
large scale production of biogas, electricity generation unit can also be evolved. The
overall performance of the biogas generation unit can be controlled by maintaining
suitable range of parameters e.g., pH, system temperature, loading rate and agitation
etc. The correct temperature range is 30–60 °C for anaerobic bio-degradation process and pH range need to be maintained at optimum loading rate is 6.8–7.2. Among
all parameters, temperature is the main concern contributing in overall production
of biogas. The length of fermentation also depends on temperature of the biogas
generation system. This temperature can also be maintained using external sources
e.g. heat of exhaust gases leaving from power generating engine driven by biogas,
electrical heat and heat yielded from any adjacent combustion unit or from biofuel
or from any of the renewable sources i.e., solar energy. The heat obtained from solar
energy, can be utilized to heat biogas digester above the ambient, may be by means
of hot water production. It is circulated through the jacket of the biogas digester.
It may reduce the time required for attaining the optimum temperature required for
biogas production. At lower temperatures, production of biogas is reduced and may
even discontinue.
An advantage associated with solar assisted biogas generating unit is that it
improves the production rate of biogas due to solar assistance. The installation cost
of such modified systems is more. It needs special attention for the operation and
31
A metal hydride based pumping system, wherein, a metal hydride is heated using
solar energy which produces a Hydrogen gas. It then pressurizes a piston which
ultimately produces a water-head up to 15 m on Sunny days (Wazed et al. 2018).
The solar thermal based pumping systems exhibited an efficiency of about 3%
in comparison to 6% of that of Photovoltaic systems. But efficiency shall not be
the prime concern in case the systems working on renewable sources. For remotely
located society irrigation purposes, a locally evolved solar thermal based irrigation
system is reported to be more cost effective and ecofriendly as compared to PV
technology (Wazed et al. 2018).
Electricity generation through solar based Micro-grid: The lowest ever rural
electricity tariff in the world is at Myanmar. Xu et al. (2019) have provided an
economic comparison of various microgrid systems e.g., Solar PV based microgrid,
diesel based microgrid, biogas based microgrid, solar PV cum diesel based microgrid,
and solar PV cum biogas based microgrid. In their study, rice husk is used as a source
for biogas energized micro-grid. Among these five types of microgrids, solar PV
based microgird generated an excess electricity of about 30% more than the local
requirements. It is attributed to the hourly variation of the incoming solar radiation
(Xu et al. 2019).
Energy Generation from Biogas: Energy can also be obtained from biogas, which
can be produced using household waste products. The disadvantage of having lesser
energy production efficiency can be improved by uniting it with a solar power. This
technology is termed as solar assisted biogas power generation unit. Biogas is generally produced from biodegradation of organic wastes/resources, by bacteria under
anaerobic condition. Such biogas generation units can be installed anywhere either
in urban area or in remotely located hilly rural area. It comprises Methane with some
amount of Carbon Dioxide, and little proportion of Hydrogen Sulphide. Based on a
large scale production of biogas, electricity generation unit can also be evolved. The
overall performance of the biogas generation unit can be controlled by maintaining
suitable range of parameters e.g., pH, system temperature, loading rate and agitation
etc. The correct temperature range is 30–60 °C for anaerobic bio-degradation process and pH range need to be maintained at optimum loading rate is 6.8–7.2. Among
all parameters, temperature is the main concern contributing in overall production
of biogas. The length of fermentation also depends on temperature of the biogas
generation system. This temperature can also be maintained using external sources
e.g. heat of exhaust gases leaving from power generating engine driven by biogas,
electrical heat and heat yielded from any adjacent combustion unit or from biofuel
or from any of the renewable sources i.e., solar energy. The heat obtained from solar
energy, can be utilized to heat biogas digester above the ambient, may be by means
of hot water production. It is circulated through the jacket of the biogas digester.
It may reduce the time required for attaining the optimum temperature required for
biogas production. At lower temperatures, production of biogas is reduced and may
even discontinue.
An advantage associated with solar assisted biogas generating unit is that it
improves the production rate of biogas due to solar assistance. The installation cost
of such modified systems is more. It needs special attention for the operation and