I have not yet discussed hybrid renewable
energy systems, which have become such a large target of research and
investment in recent years, especially as part of rural electrification
initiatives. In previous posts I’ve generally focused on looking at the exciting
growth of solar energy applications in rural areas. But a lot of recent research
has shown that using different forms of renewable energy together (wind, solar,
biomass etc.) in integrated hybrid systems can be vastly more efficient and
environmentally friendly.
Fadaeenejad et al. (2014) recently assessed the viability of combining renewable power sources to
electrify a rural village in Malaysia. They found that, especially when combining
solar photovoltaic (PV) with wind and battery power sources, hybrid renewable
systems can be a reliable solution and cost-effective for rural
electrification.
Stand-alone hybrid renewable energy systems
commonly take the form of solar PV-wind-battery systems and PV-diesel-battery
systems. Different sources can be effectively used in combination; for example,
batteries can be used to store energy produced by PV panels to help met
required demand round the clock, and wind can act as a source of energy when
solar is unavailable at night. When compared to wind and PV systems in
isolation, these hybrid systems seem to be more reliable and demonstrate
optimal minimisation of CO2 life cycle emissions and net present cost,
specifically relating to the levelized cost of energy (Bernal-Agustin & Lopez, 2009).
It is thought hybrid systems perform best when photovoltaic panels/generators
are included, and solar may generally be a more important source of energy over
other sources within such systems (Lopez et al., 2011).
It has been shown hybrid systems are
economically viable in off-grid areas (Deshmukh & Deshmukh, 2008;
Valente & Almeida, 1998. PV-diesel-battery
systems may be especially suited to areas with warm climates (Shaahid &Elhadidy, 2003).
It is important, however, that issues such as long-term sustainability, reliability
and minimization of carbon emissions are considered as well as
cost-effectiveness and economic viability.
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| PV-wind-diesel-battery hybrid renewable energy system (Fadaeenejad et al.,2014) |
Designing, controlling and optimising hybrid
systems may be complex and difficult, and efforts need to be made to ensure
such systems are designed to perform effectively and reliably in rural
contexts, both in isolation and as part of mini-grids. However, recent
developments in the technology and effective application of hybrid systems hold
much promise.
