Hybrid systems and concluding comments

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.

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.

Fossil fuels, and nonrenewable grid systems, are likely here to stay for at least a while longer. But this doesn’t mean there isn’t an exciting future ahead for renewables. Integrated hybrid renewable energy systems are indeed an exciting advancement in renewable technology, but perhaps what is more exciting is that they are just one avenue of research being taken in a wider, expanding movement towards rural sustainability. There are now efforts being made all over the world to better construct renewable, sustainable systems of rural electrification. The long-term success of these efforts depends on greater investment and continued research and development, and it is crucial that rural electrification schemes are better designed to fully and effectively meet sustainable development objectives. Beyond this, there is still much else to look forward to. As I hope I have shown in this blog, off-grid renewable energy is just part of the growing network of innovative opportunities shaping the sustainable future of rural areas.