Increasing environmental concerns, consumer expectations of reliability, better quality of power supply, and the improving economics of distributed energy resources based on renewables all make the microgrid a viable and increasingly widespread proposition. Hybrid microgrids that use diverse energy sources including solar, wind, biomass, and energy storage batteries are superior to single source microgrid systems. But how can one go about deciding which combination of renewable sources is best?
At Oorja we have bet on locally and abundantly available crop waste and solar energy being the best resources to power rural communities. In this post we explain why.
Agricultural waste: Carbon negative or a way to reverse CO2 emissions
- Agricultural waste disposal is becoming a serious problem. If left to decompose, it emits methane and leachate. Open burning of crop waste in fields emits billions of tons of black carbon into the atmosphere which is a major contributor to climate change. Improper management of agricultural waste is contributing to climate change, water and soil contamination, and local air pollution.
- Agricultural waste is widely and cheaply available and can be sourced locally. According to UNEP’s findings, 5 billion metric tons of biomass are generated every year from agriculture. This is the thermal equivalent of about 1.2 billion tons of oil - approximately 25 percent of current global production.
- It offers local business opportunities, creates jobs, and supports the rural economy. Farmers can generate extra income by selling agricultural waste for productive purposes and the char that is a byproduct of gasification can be sold by local micro-entrepreneurs for various agricultural and industrial applications. Furthermore, biomass energy production is more labor intensive than other energy sources. This translates into job creation, transferable knowledge and skills, local innovation and, therefore, a boost in rural economic development.
- It reverses CO2 emissions. Currently this agricultural waste is a source of greenhouse gases: burning it produces CO2, and letting it decompose releases methane, a gas which, pound-for-pound, contributes over 25 times more to global warming than CO2.
- Biochar, the residual charcoal, is an excellent natural soil enhancer. It helps restore degraded soils and increase crop yields by improving water and micro-nutrient retention capacity. Moreover, it helps sequester carbon by absorbing CO2 from the atmosphere and sinking it safely into the ground for thousands of years.
- Char has many other productive uses. Among other things, it can be used for water purification, as fuel cookies in clean cookstoves, insulation for buildings, filters in sewage plants, a silage agent, and as a feed supplement.
The benefits of converting biomass into energy are manifold. However, sometimes plant maintenance issues or the seasonal availability of the feedstock can compromise the supply of electricity.
We want to ensure reliable and uninterrupted supply so that rural households and small-scale businesses that depend heavily on energy provision for their production get the power they need. That’s why we aim to incorporate solar technology together with biomass in our decentralized energy systems.
Biomass from agricultural waste is great but complementing it with another source, like solar, makes energy provision more reliable, affordable, and sustainable.
Why do we choose solar?
- Solar is as natural a source of power as possible to generate electricity and has no emissions during operation.
- Sunlight is widely available in India. With about 300 clear, sunny days a year, India's theoretically calculated solar energy incidence on its land area alone is about 5,000 trillion kilowatt-hours (kWh) per year (or 5 EWh/yr).
- There are continual advancements in solar photovoltaic technology, increasing efficiency and lowering the cost of production, thus making it cost-effective for consumers.
- Solar plants are easy to operate and require less maintenance. High school graduates and unschooled women can be trained to run and maintain the plants, bringing new skills into the community. Once the solar photovoltaics have been installed and are working at maximum efficiency, there is only a small amount of maintenance required each year to ensure they are in working order.
Oorja campaigns for the use of hybrid solar and biomass-powered microgrids to tackle energy poverty, agricultural waste disposal, soil degradation, and climate change. 200 million tonnes of crop waste and 300 sunny days a year are available in India without being put to productive use. Clean energy is fundamental to poverty reduction and a critical enabler of sustainable development. In 5 years, we aim to reach 1 million underserved people and to save 1 million tonnes of CO2 emissions - equivalent to wiping out the annual emissions of one large coal-fired power plant!
If we are resolute about combating climate change and heading towards a carbon-neutral planet over the course of the next several decades, a great deal of innovation will be required. The energy sector will have to be entirely transformed from the bottom up; existing processes of electricity generation from renewable energy sources will need to be drastically improved and implemented on a massive scale. No one solution by itself will be able to meet the demands of rural communities that lack access to the national grid, but hybrid solar and biomass microgrids appear to be the lowest hanging fruit, particularly for those at the bottom of the pyramid.
- 55 Uses of Biochar: http://www.ithaka-journal.net/55-anwendungen-von-pflanzenkohle?lang=en
- U.S. Congress, Office of Technology Assessment (1992) Fueling Development: Energy Technologies for Developing Countries, OTA-E-516