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Reduce post-harvest loss with Energy Free Cool Storage

Simple 'root cellar' cool storage technology that optimizes agriculture storage life and quality without the use of electricity.

Photo of Sophie Aigner

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EXPLAIN YOUR IDEA

In Zambia, 60% of the labour force works in the agricultural sector and 80% of people living in rural Zambia depend on agriculture for their livelihoods. Many of these farmers grow horticulture produce, which suffers huge losses each year due to a lack of viable storage technologies available. The Energy Free Cool Storage will address this problem among Zambian farmers by providing an affordable, easy to maintain technology that is not dependent on existing infrastructure systems. At a depth of eight to twelve feet underground, the subterranean, 'root cellar' Energy Free Cool Storage will provide a cool storage environment with 90-95% humidity and natural ventilation to keep the proper temperature. The simple technology consists of three parts: (1) a scalable storage “tank” for agricultural output, (2) two ventilation pipes to naturally facilitate air circulation, and (3) an entryway/hatch for easy and secure access. The technology will be further refined from feedback through an HCD process with target farmers and aggregators, then piloted with vegetable farmers in Zambia. After proof of concept, price-point, and specifics are confirmed, the technology will then be scaled and a second version adapted to target marketplaces, who currently have no cool storage facilities. The technology will be sold through inclusive sales models and eventually scaled to other relevant countries throughout Africa. See Attachment 1 for more info on technical details and financing.

WHO BENEFITS?

1. Farmers and aggregators - Rural farmers who grow vegetable crops can now store them in the Energy Free Cool Storage owned by the aggregator. With this technology, they will be able to store produce for an extended period of time, giving them the power to facilitate fair transactions with buyers and transporters. The aggregator is paid per box of produce stored. 2. Marketplaces - Markets currently have no cool storage. This will allow markets to keep produce fresher longer, reducing loss.

WHERE WILL YOUR IDEA BE IMPLEMENTED?

The Energy Free Cool Storage technology will be piloted and designed for Zambian farmers. After proof of concept is established in Zambia, the technology will be scaled to other relevant African countries.

ARE YOU IMPLEMENTING IN AN ELIGIBLE COUNTRY?

  • Yes

EXPERTISE IN SECTOR

  • I’ve worked in a sector related to my idea for over a year

EXPERIENCE IN IMPLEMENTATION COUNTRY(IES)

  • Yes, for more than one year.

TELL US MORE ABOUT YOU!

Energy Free Cool Storage is the collaborative research and development effort of a Zambia-based agriculture technology engineer, a Zambia-based agriculture and social enterprise consultant, and a supply chain and operations expert with experience in numerous developing countries.

IS THIS IDEA NEW FOR YOU OR YOUR ORGANIZATION?

While the team members are all experienced in agriculture technologies, this is the first initiative in which these three specific individuals are coming together to prototype and explore the market opportunities behind energy-free cool storage technology. Sophie Aigner currently works as an agriculture enterprise consultant in Zambia for a small business that is creating an inclusive, easily accessible mobile platform to connect smallholder farmers with the greater agriculture market. She has also done agricultural business development for over 2 years. Festus Hanunkuni is a Zambian agriculture engineer, and has had a hand in creating various agricultural technologies, including drip irrigation equipment and solar pumps. Brendan Somerville is a supply chain and entrepreneur expert, and has worked with various agriculture technology start-ups globally. While the Energy Free Cool Storage is a new idea for us, it is something that has been of interest to all team members for quite some time and aligns naturally with our experience.

HOW IS YOUR IDEA UNIQUE?

Energy Free Cool Storage is unique in the following ways: -Does not require any energy source. This is especially advantageous in southern Africa (namely Zambia and Zimbabwe), where loss of power is up to 10 hours daily. -Minimal operating costs. Once installed, all the farmer, aggregator, or market needs to do is add or remove agriculture items. -Scalability. Model 1 will target aggregators and farmers, while Model 2 will scale to accommodate the needs of markets. -Is the product of a diverse Zambian-American partnership with unique resources. -Aims to disrupt farmer-market trading behavior. We are unaware of underground storage initiatives of similar scale being implemented in Africa. However, the walk-in “root cellar” concept has been around since the 17th century. This Storage will lay the groundwork for small farmers to build their negotiating/decision making power and ways of doing business, and will open them up to a world of agriculture resources. Taking crop to a 'flooded' market will no longer be the only option. Farmers can now choose when to take to market and what market to sell to, as well as have time to negotiate affordable transport.

WHO WILL IMPLEMENT THIS IDEA?

The founding team will implement this idea: Sophie Aigner: A Zambian-based business development, market facilitation and R&D liaison, Sophie will match customer needs with product development and execute on the ground. Festus Hanunkuni: A Zambian engineer, Festus will coordinate engineering, design and installation, and product testing. Brendan Somerville: With ample ag start-up experience, Brendan will work full time on this project and lead fundraising, product development, and expansion.

HOW HAS YOUR IDEA CHANGED BECAUSE OF BENEFICIARY FEEDBACK?

1. Originally, the Model 1 prototype was planned to target the individual farmer. However, after beneficiary interviews with both aggregators and smallholder farmers, it is clear that farmers prefer to have an Energy Free Cool Storage technology owned by a local aggregator in which they can rent storage space as needed. This will now become Model 1, which serves both aggregators and farmers. 2. The farmers and aggregators interviewed expressed the desire to have stronger relationships with contractual buyers in order to build business and capitalize on the investment that would be made in the Energy Free Cool Storage technology. This will be an aspect that our team will integrate into the business model. 3. Average farmer loss is 25% of crops harvested, and can often go above this depending on resources, transportation, and oversupply of produce at the market. This is even higher than we originally estimated, and gives us an even stronger platform to create demand for the Energy Free Cool Storage, with 100% of interviewees saying they would be willing to pay (various amounts) to rent storage space in a community storage technology.

WHAT ARE SOME OF YOUR UNANSWERED QUESTIONS ABOUT THIS IDEA?

1. Which construction material has the appropriate balance of cost effectiveness and structural integrity? 2. What are the highest benefits that farmers and aggregators experience from using Energy Free Cool Storage and how do we best communicate these widely across Zambia? 3. What is the best shape to provide strength against soil pressure and ease of installation, given Zambian soil conditions? 4. What is the ideal installation depth in Zambia to obtain optimal cooling temperatures? What additional inexpensive add-ons can help maintain stable temps (i.e. tents)? 5. How will this technology affect the ways Zambian farmers sell their produce? 6. What financing model works best?

WHY DO YOU THINK THE PROBLEM YOUR IDEA SOLVES FOR HASN'T BEEN SOLVED YET?

1. Most companies have focused on energy-powered cooling, which is not supported in much of rural Zambia due to off-grid farmers and extreme load-shedding. 2. Small African farmers don't fit into the ideal customer income level for most investors. Building such a technology requires heavy up-front work and funding; it is a long term investment with lengthy ROI periods; and it requires willingness to take on risk - all deterrents to traditional investors. 3. Farmers have adapted to trading without cool storage - for example, growing less produce so they don't lose out on 'flooded' markets. The EFCS aims to disrupt the way farmers trade to drastically increase their market participation.

WHAT WOULD YOU ULTIMATELY LIKE TO ACHIEVE WITH THIS IDEA? WHAT IS YOUR NEXT STEP TO GET THERE?

The longview is to revolutionize continent-wide agriculture storage in Africa. Underlying this longview is enabling small African farmers to participate in the global agriculture industry. There is huge opportunity for agriculture in Africa and we can help farmers grow their businesses to levels where they can actively participate in the African agriculture trade by equipping them with the needed tools and resources. The next step: obtain funds to build a prototype and get it to market.

MEMBERS OF MY TEAM HAVE BEEN WORKING TOGETHER FOR:

  • More than a year

MY INTENDED BENEFICIARIES ARE:

  • Within 50 km of where our team does most of its work

MY ORGANIZATION'S OPERATING BUDGET FOR 2015 WAS:

  • We didn't have an operating budget

Energy Free Cool Storage delivers cool storage for agricultural outputs by leveraging the root cellar concept and a design which does not rely on coolants, electricity, or solar power. Root cellars are underground structures that provide low and steady temperatures as well as stable humidity. By taking advantage of subterranean geothermal soil properties, root cellars create an effective environment to ensure the stability of three key produce storage variables: humidity, temperature, and ventilation. At a depth of eight to twelve feet underground, Energy Free Cool Storage will provide a cool storage environment with 90-95% humidity and natural ventilation to keep the proper temperature, reduce excess humidity, prevent rot and mold, and remove ethylene gas.

The simple technology consists of three parts: (1) a scalable storage “tank” for agricultural output, (2) two ventilation pipes to naturally facilitate air circulation, and (3) an entryway/hatch for easy and secure access. The storage tank is where farmers, aggregators, or marketplace actors can efficiently store their produce. The pilot version of the Energy Free Cool Storage will be designed for individual farmers, while future versions will scale in size to be sufficient for aggregators and marketplaces. The Model 1 prototype will be built and tested specifically for Zambian tomato farmers and will have a 4,000 liter storage capacity. The ventilation is provided by two simple polyvinyl chloride (PVC) pipes. Although both pipes will initiate above ground, one will terminate at the top of the storage “tank” and one will terminate at the bottom of the storage “tank.” This creates a siphon in which fresh air is introduced and stale air is vented out. Wire mesh and a vent cap will prevent moisture and pests from entering through the ventilation system. A sealable hatch and small ladder will allow entry and exit from ground level. On larger models, a stairway will be introduced. Unlike many storage devices, Energy Free Cool Storage is a closed environment which facilitates the secure storage of crops. Installation method depends on size of the “tank.” The pilot version can be installed with a shovel and manual labor.

While initial models take advantage of the simplest version of a “root cellar,” future models such as the Model 2 for aggregators and markets can include solar-powered ventilation and lighting, thermometers and hygrometers, and advanced shelving and warehousing systems.

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Attachments (2)

Attachment 1_EFCS.pdf

The purpose of this document is to elaborate on questions posed in the comments section and provide additional clarification on key aspects of Energy Free Cool Storage.

UX Map_Energy Free Cool Storage.pdf

This is the early-stage User Experience map for Energy Free Cool Storage.

21 comments

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Comment
Spam
Photo of William Lanier
Team

Hello Sophie,
It is a relief to see the 17th century concept of root cellers delivered to Africa.
My experience designing root celler suggests that a roof is needed over the entrance to prevent rain from 50 - 100 year events from entering the hatch.
Extending this roof or any structure or ground cover that reduces the amount of sun reaching the soil in the area above and around the storage tank with help lower ground temperatures and the chance of erosion. The shade is why a root celler is often  incorporated into utility buildings, warehouses etc. 
The floor of the root celler should be designed with a depression or sump that accepts the intake of a pump for emergencies.
Congratulations on suggesting root celler for Africa,
William
Storage Rights To Reverse PHL
Jobs for Youth To Reverse PHL

Spam
Photo of Sophie Aigner
Team

Hi William Lanier ,

Many thanks for your helpful comments - we will definitely take those into consideration.  It would be great to get in touch with you as we are finalizing the design of the root cellar as it seems you have experience doing it yourself.   We are looking for all the experience and input we can get.  If you don't mind, please send me an email at aigner.sophie@gmail.com and we can connect further.

Best regards,
Sophie Aigner

Spam
Photo of William Lanier
Team

Hello Sophie,
You should see my email and happy to join your team.
William

Spam
Photo of William Lanier
Team

Hello Sophie Aigner,
William (NeverIdle) hopes you and the root cellar are doing well and wish to invite you to the "1st All African Postharvest Congress and Exhibition (March 28 - 31) Nairobi"
<http://africa-postharvestconference.uonbi.ac.ke/>. We hope to meet and discuss more about Moisture meters and testing to Reverse Grain Postharvest Loss."
Regards,
William

Spam
Photo of Lisa Kitinoja
Team

It would be helpful if you could include some information regarding the average soil temperatures in Zambia at the depth that your root cellar will be installed.  For example in the Northern hemisphere the soils at 2m depth tend to be about the same temperature as the average surface water temperature (of a river for example) -- perhaps 15 to 18C.  

Spam
Photo of Sophie Aigner
Team

Hi Lisa Kitinoja ,

Thanks for your comment.  We will add some information on this in the actual body of our submission, but just to give you an idea of the some of the research we have been doing, I will put more detail here.

While we have not been able to conduct a subterranean soil temperature experiment in Zambia because we do not have financial resources, we are using data from academic journals, previously conducted experiments, and underground home resources. At about 2 meters below the surface, you are correct to conclude that ground temperatures will fluctuate seasonally almost with air temperatures (this information was confirmed by a U.S.-based geotechnical professor). However, at lower depths -- 3 to 4.5 meters -- ground temperatures generally stabilize around the mean annual air temperature. In an earth-sheltered home journal, a year long test (image attached in submission pictures) showed the differences in ground temperatures at depths of 2.5, 5, 7.5, and 10.5 feet below the surface. The results demonstrate that there is a marked difference between 2 and 3 meters and at each interval their sensors tested. Thus, our Zambia prototypes will likely be over 3 meters below the surface, depending on the specific installation location. Initial testing might find that even lower depths are required for stabilization closer to 10-14 degrees C. In other African countries, the installation could be successful much closer to the surface at 2 to 3 meters.

In fact, data published by Olgun and McCartney’s 'Outcomes from International Workshop on Thermoactive Geotechnical Systems for Near-Surface Geothermal Energy: from research to practice' demonstrates the clustering of subterranean ground temperatures at 10.6 degrees C, the average annual temperature for the study’s location in Virginia, at depths of approximately 4.5 meters or below. Of course, the average temperatures of Zambia is higher than Virginia, so the storage temperatures will be higher at the same depth. That being said, it is important to take into account our key crops targeted with this technology (with one of the biggest crops being tomatoes), and to note that many of these crops suffer from storage temperatures below 10 degrees C for a period longer than 6 days.  These are all things we are taking into consideration.



A key component, in addition to just the temperature figure, is the stability of temperatures and humidity levels that can increase the storage life of produce long enough to sell. Even at temperatures higher than 10 degrees C, the stabilization of temperatures and humidity will increase the quality and life of post-harvest outputs.

Although we have yet to find specific information on subterranean temperatures in Zambia, we are still reaching out to agricultural research centers to see if we can get some more information on this before 21st June, at which time we will update out submission with more information.  Regardless, we will budget the soil temperature testing into our prototype framework.

Please let me know if you have any other questions or thoughts on this, as we welcome any feedback you have.

Kind regards,
Sophie

Spam
Photo of Lisa Kitinoja
Team

Thank you Sophie, I think your proposed project is much enhanced by having some of these technical details on temperature, RH%, soil depths, etc. included for us to read about.  Best wishes with your excellent IDEO posts.  LK

Spam
Photo of Sophie Aigner
Team

Thanks Lisa Kitinoja for the recommendation.  I have included an attachment with information on technical product details such as these as part of the submission.  Your feedback has been very helpful.

Kind regards,
Sophie 

Spam
Photo of Chioma Ume
Team

Hi Sophie,

The Amplify team and our experts has some feedback for you:

I'm glad there was lots of research done for the service design and how business models could be built.

Have you created any prototypes  of this idea? Are you able to share them with us? 

How will farmers find out about this service? How do you envision farmers being able to pay for this product? 

Looking forward to learning more! 

Spam
Photo of Sophie Aigner
Team

Hi Chioma Ume ,

Thanks for the questions and comments.  I will add some of this information to the body as well, but here is some more information for you.

Regarding prototypes, we unfortunately have not been able to build our first prototype yet as we have not yet obtained funding.  As we work to obtain funding, we have been researching all aspects important to creating prototypes - such as looking as possible roof types and structures to adhere to soil pressure and subterranean soil temperatures in Zambia; getting farmer feedback on prototype design; identifying what building materials could be produced locally here in Zambia and what would need to be imported; scoping out locations to serve as our prototype hub, etc.

How will farmers find out about this service?

As explained in the Beneficiary Feedback phase, the model that we will be prototyping is aimed at community aggregators who will rent out the cold storage to farmers. Through iDE Zambia (where two team members have professional connections), there is a network of aggregators that are trained as Farm Business Advisors (FBAs). These FBAs are rural-based community members who are highly trained by iDE field officers in selling inputs, providing extension services, serving as aggregators to sell bulk amounts of produce to markets, and many more services. Then, FBAs are linked to key private sector players, such as seed suppliers and buyers, and they make commission from the private sector on services performed on their behalf. Each FBA has on average 80-100 farmer clients in his/her community that s/he serves. iDE Zambia currently has over 250 FBAs throughout the country and this number is growing rapidly. The FBA network will be our primary channel of getting the word out to farmers. We will prototype the first model with a number of FBAs, and after proof of concept is developed, we will market the technology to other FBAs and farmers throughout Zambia to scale the business. We will also use channels such as local radio, and adverts on relevant platforms to get the word out to farmers and aggregators about the technology, but these will be secondary to the FBA network, which is our biggest advantage in bringing this product to market.


How do you envision farmers being able to pay for this product?

There are two payment models that have to be considered for this technology. One is around the aggregator (who in the beginning stages will be an FBA as well) who will purchase the technology, and the other is around the farmer, who will rent space in the technology. The most important and likely most challenging payment model to determine is that around the aggregator. There is the more traditional route of partnering with Micro-Finance Institutions (MFIs) to provide loans to aggregators which are paid back over time, but these usually have high interest rates and are structured wholly to benefit the institution and not address the needs of the consumer.  Taking that into account, there are two options that should be prioritized for pilot in the distribution of this technology.


1. In this model, the technology is not bought directly by aggregators, but instead by bulk produce buyers. In this model, the bulk buyers would sign a supply contract with the aggregator to buy a stated amount of produce by a stated date. The EFCS business team would ensure that the right pieces are in place to allow aggregators to meet these amounts, such as extension support, seeds, fertilizers, and equipment. Then the aggregator would pay off the technology (for very low or no interest) to the bulk buyer through the payments made to the aggregator for produce. After the payment period has ended, the aggregator would be the rightful owner of the technology. Models such as this where bulk buyers are paying for the cost of technological inputs are becoming more and more common in Zambia, and this could be a viable financing model for the EFCS. An added benefit is that the aggregator would have a secure market to which to sell his/her produce, reducing loss even further.


2. In this model, the technology is given to the aggregator on receipt of a down payment, and paid back to the EFCS business team over a mutually agreed upon term. This again assumes low or no interest, depending on the design of the payment terms, and would again include the EFCS business team linking aggregators and farmers to the required inputs to successfully build their income through produce. 


For farmers, the prices they would pay will be affordable for them (such as 2 ZMW - 5 ZMW per crate of vegetables). This would mostly likely be paid to the aggregator at the time of sale of produce. This speaks to the design principle of making these technologies extremely affordable, and more than that, extremely durable. Aggregators will see the most value in a product that lasts 5+ years and can bring in return on their money in 2 years or less.

Spam
Photo of Chioma Ume
Team

Hi Sophie, thanks so much for the clarification! Sorry if I missed this anywhere, but do you have an estimate about what this might cost? (I know there would be savings with scale and adoption, but as an initial rough estimate?)

Spam
Photo of Sophie Aigner
Team

Hi Chioma, we have not detailed specific costs for the pilot model, as it depends on the following factors:


(1) Unit size



(2) Required depth (location-specific)



(3) Availability of existing/used/reclaimed components that can be incorporated into the design (for instance, the model of shipping container farms uses a commodity shipping item readily available during global economic downturns or import/export imbalances).



(4) Structural and materials engineering input. This would allow us to determine the appropriate design and strength so as not to over-engineer and thereby save costs.



However, using underground storm shelters, pre-existing structures that could be converted (water storage containers or shipping containers), or pre-fabricated ground fridge designs as a proxy for potential costs, a rough estimate would be $4,000 to $10,000. In analyzing this high capital expenditure, it is important consider extremely low operating costs, the potential for shared costs/rents, payment plans which spread the costs over time, and the increased value of agriculture outputs created by a technology of this scale. For more information about the potential marketing/business model, please take a look at our proposals and let us know if you have any questions.

Spam
Photo of Chioma Ume
Team

Ok, sounds good Sophie! Thanks for the details :)

Spam
Photo of Chioma Ume
Team

Hi Sophie,

I notice you haven't filled in the answers to the new phase questions yet. Friendly reminder to do so before the phase ends next week. Remember that the 'full description' field won't be visible to any of your readers.

Cheers!
Chioma

Spam
Photo of Sophie Aigner
Team

Hi Chioma Ume ,

Many thanks for the kind reminder.  I just finished our beneficiary feedback process today and have updated the entry with answers to the new phase questions.  I look forward to hearing your feedback.

Cheers!
Sophie

Spam
Photo of Chioma Ume
Team

Looks great! Thanks! Will anyone on your team be focusing full time on this idea? 

Spam
Photo of Sophie Aigner
Team

Hi Chioma Ume  ,

Thanks for your feedback!  Yes, Brendan Somerville will be full time from the beginning and I will be full time starting early 2017 (as funds permit).  I have updated the submission to include Brendan's full time status.

Kind regards,
Sophie

Spam
Photo of Chioma Ume
Team

Helpful, thank you! 

Spam
Photo of Sifa Enock
Team

Awesome, you have done the nice work, let me add my contribution on the question of how is your idea unique? This idea uniquely suited to do this project because has done the pilot assessment to community members and receive their emotional and feedback on this idea and voice of many people was in cool storage technology as the solution of our challenge,  this likely to be successful in the campaign.

Spam
Photo of Sophie Aigner
Team

Hi Sifa Enock , 

Thanks for your feedback! Our main focus is building a product that is needed, wanted, and accessible (in terms of affordability and actual physical accessibility) to smallholder farmers.  We came across this idea after the extensive load-shedding first hit Zambia in mid 2015.  Thanks for your feedback and support!

Best regards,
Sophie 

Spam
Photo of Vickie Aigner
Team

Brilliant idea!