Being cool with waste

Glen Paul: G’day, and welcome to CSIROpod. I’m Glen Paul. In times past to keep your food refrigerated and preserved you’d call upon an ice harvester to carry in blocks of ice from somewhere cold. While refrigeration systems put an end to that, there are still places in the world that don’t have access to any form of cold storage.

The widespread lack of access to electricity in rural areas of India means that refrigeration facilities are few and far between, leading to millions of tonnes of fresh produce spoiling before it reaches consumers. To overcome this CSIRO partnered with TERI, The Energy and Resources Institute, in India, to develop an ingenious system that combusts waste products to generate electricity to power refrigeration.

Called the Cool Village Power project the system is set to revolutionise life in many tropical countries, like India, where agricultural produce has the potential to spoil at the point of production due to inadequate storage facilities. Joining me on the line to discuss the project is CSIRO’s Dr Subbu Sethuvenkatraman. Subbu, how does the biomass powered refrigerator work?

Dr Sethuvenkatraman:The biomass system actually uses locally available biomass material to convert its energy into electricity, and this electricity actually is used to power the villages, as well as to run cold storage. The cold storage runs with a compression system, and whenever the biomass is available you will basically be producing both electricity and cold storage for the villages.

Glen Paul: OK. It kind of reminds me of a scene in the science fiction movie Back to the Future, where they stuff banana peels and other household waste into Mr. Fusion, creating electrical power for the time machine. Obviously this is somewhat different, but where did the idea for it come from?

Dr Sethuvenkatraman: Biomass based power generation has been, you know, explored before, and our partner, TERI, in India have been working on a technology of this sort, and they have their unique approach for generation of power from all the biomass, and CSIRO having expertise in cold storage, basically we combined it to see if we can generate electricity and cold for villages which do not really have access to both of them.

We have this cold storage under point of production. You store these vegetables pretty fresh, and that helps to save lots of loss. Also the farmers can directly approach the cold storage rather than, you know, going through let’s say middle man in accessing this cold storage facility.

The second benefit with this approach is in India, and probably there are many countries similar to this where we may not have access to electricity in villages, so this system of biomass refrigeration actually solves both the problems. You know, you provide electricity which will actually help the farmers in terms of their quality of life, providing them electricity for their household equipment, and some have used electricity even for storing their produce, so it actually benefits them in both ways.

Glen Paul: Right. So the biomass gasifier is a separate power source, you just plug the refrigerator into it.

Dr Sethuvenkatraman: Biomass produces electricity, and electricity could be used for various applications, like what we have done in these villages basically, providing lighting, and mobile phone charging, and some of the power points for TVs and things like that.

Glen Paul: And what’s the reason behind a biomass power supply over solar?

Dr Sethuvenkatraman: We can actually use solar power as well. In fact one of the previous projects which we implemented, again along with TERI, actually uses solar power as well as biomass. So there are various approaches, and in fact, you know, one of the objectives of this study will be to see which might be the best approach. We could either use solar power and even the waste heat from the biomass to generate cooling, or we could just simply use the electricity from the biomass to generate cooling.

So in fact one of the objectives of our work is also to understand which might be a better option, given the rural population and the solar availability, and even the biomass availability.

Glen Paul: And how much biomass is required to keep the system running?

Dr Sethuvenkatraman: The system is actually about 50 kilowatts electricity generation, and we are looking at somewhere about 60 kilograms per hour of biomass, that is what we will be using to generate electricity.

Glen Paul: OK. And is there any limitation to the type of refrigeration system that can be used?

Dr Sethuvenkatraman:The refrigeration system, you know, being able to store vegetables and fruits obviously needs to generate really close to freezing point. There are specific refrigerants that can actually do this, and we are in fact looking at some of the options of having a cold storage that can really take multiple types of vegetables and fruits and that.

Glen Paul: So where is the system being trialled, and when will it become commercially available?

Dr Sethuvenkatraman: We have currently installed this system at two villages in Uttar Pradesh State of India to completely electrify villages. This demonstration has been completely funded by AusAID. TERI and CSIRO are the technical partners in this program. This is basically a demonstration prototype at this location. Once we understand the financial viability and technical viability of this approach this can certainly be scaled up, and you know probably duplicated at multiple locations, because there are many more locations which will utilise a benefit from such an approach.

So this could certainly be scaled up to other locations pretty soon, once we understand the financial viability, as well as the technical functioning of this approach.

Glen Paul: Ingenious stuff, and very cool, to use a bit of a pun. It certainly will go a long way in feeding a lot of people. Thanks for discussing it with us, Subbu.

Dr Sethuvenkatraman: Thank you.

Glen Paul: Dr Subbu Sethuvenkatraman. And to find out more about the research, or to follow us on other social media, just visit www.csiro.au.