Archive for the ‘Urban Ag’ Category

Poo gurus | Rebranding ‘waste’ instead as ‘resource’

First things first. I think the human race would be more inclined to participate if ‘waste’ was rebranded ‘resource.’

In light of the exceptional drought in California, and the ‘slated’ increase in population for space ship Earth, INDEED, water management is paramount. To supply a great deal of the current and future inhabitants with water management flush and discharge sanitation systems is not sustainable or pragmatic long term.

Overall, I think what is needed is improved education on the whether (and how) local taboos surrounding excreta change when it is presented as a resource versus a threat. And so, I propose it needs to be rebranded with the operative ‘resource’ instead of ‘waste’.

Altho the aversion to humans’ excreta has been a major reason that has limited the spread of disease, what is not widely known is it was not until the 19th century that the links between bacteria and disease were fully understood. However, what we know now, is humanure, managed properly, is a rich, sustainable resource as a soil amendment and fertilizer for food propagation that doesn’t require a lot of water input–but today, has been mostly dismissed as a viable resource in most developed nations.

Over the past few decades, there has been a great deal of interdisciplinary research on the technical feasibility and social acceptability of two very different approaches that could be applied to managing human excreta/humanure; ‘sewer avoidance’ (separation at source and the use of on-site remediation methods e.g. composting toilets AKA ecosan/ecosanitation toilets), and approaches that dispose of sewage sludge using technologies like reed beds and ‘waste to energy’ (gasification and anaerobic digestion)–essentially, using humanure as a means to transfer filth into food.

Although Pliny’s Natural History, Book XXVII stated that “human excretions are the best possible fertilizers” (Laporte, 2000, p. 152), it received relatively little attention from scholars until the fourteenth century when Crescentius of Bologna first published his Opus ruralium commodorum in 1307. According to Laporte, “the symbolic equation of money and shit” (Laporte, 2000, p. 33) was formally registered when the Opus was translated into French, in 1532, under the title “Prouffits campestres et ruraulx”. The value of human waste as a fertilizer was again ‘rediscovered’ in nineteenth century France as the hygienists’ movement emphasized the superiority of human excrement and physicians urged agricultural communities to “incite serious contemplation amongst growers in a region whose agricultural fame rests on the very rational use of human secretions in their most natural state.” (Bertherand, 1858, quoted in Laporte, 2000, p. 120).


Laporte, D. (2000). History of shit. Cambridge MA: MIT Press. (translated by Benabid N and El-Khoury R).

Poo gurus? Researching the threats and opportunities presented by human waste, Sarah Jewitt, School of Geography, University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom


Baltimore Food Hub

Baltimore, Maryland might have a high crime rate, but this city is visionary. Like a few other municipalities in the USA, Baltimore is leaps and bounds ahead on what needs to be accomplished with regard to food security. But it should be no surprise. Johns Hopkins University (JHU) revolutionized teaching and research.

For years, since I returned from my six months in the field WWOOFing back in 2011, I have been asking, “When the cost of petrol becomes prohibitively expensive, how will we address replenishing the food markets/grocery stores?”

The Baltimore Food Hub will be the first of its kind in the Region. As a food campus, every tenant will get the support and access they need to be focused on growing the food economy.

An innovative concept in promoting local and regional foods on a 3.5 acre campus in E. Baltimore, that is offering entrepreneurs resources to scale their mission.  This concept certainly adheres to PREPARE. RESPOND. ADAPT.


For quite some time now, I have had my doubts about some advances in technology and the definition of what really constitutes progress?

Today, modern glass greenhouse require massive inputs of energy to grow crops out of season. This is considered progress? This energy loss is due to the fact that every square meter of glass, triple glazed included, loses ten times as much heat as a wall, a thermal mass.

Producing crops in temperate regions did not originally involve glass greenhouses, instead thermal masses, fruit walls, were utilized. These thermal fruit walls stored heat from the sun for nighttime use, and are installed with insulated mats rolled out over the glass covers during the night or cold weather; passive solar buildings in the true sense.

Kris deDeker recently posted up a nice exploration of the utilization of passively designed fruit walls that were highly utilized in urban farming up until the late 19th century in Europe.

Fruit Walls: Urban Farming in the 1600s

This labor-intensive practice required a deft, skilled hand for maintenance. But cheaper, less-labor-intensive produce was imported due to the railways eventually took over.

I understand, some of these passive farming practices are still used in Korea. And the Chinese use passive solar greenhouses that are heated year round with only solar energy. Of course performance will be predicated on the greenhouse design, the location (latitude), and on the local climate.

According to Kris, produce grown in a passive greenhouse industry would take up two to three times as much space to produce the same amount of food. But do we really need to be eating so much anyway? 

Another challenge is it is a best-practice is to have a CO2-level that is at least three times the level outdoors to increase crop yield. When no there is no CO2 byproduct from the combustion of fossil fuel based heating systems inside the greenhouses, another source is required. Provided a structure is well insulated, compost from the manure of livestock and fish in an aquaponics system can serve this purpose. A compost heat recovery system producing hot water could be pumped through a radiant floor. So compost can serve a triple purpose; CO2 production,  heating, and soil enrichment.

Talk about a GREAT food propagation practice to re-institute in the urban environment. Get me to a warehouse space!

Fruit Wall Greenhouse

Greenhouse built against a serpentine fruit wall. Source: Rijksdienst voor het culturele erfgoed.


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An engineering generalist with an understanding of sustainable development whose skills set are typically comprised of an amalgam of mechanical and electrical engineering. One who is able to design and assemble systems and components that are comprised of more than one renewable energy (RE) technology i.e. solar, wind, hydro-kinetic (ocean/wave/micro-hydro), biomass, hydrogen fuel cell, geothermal and storage (battery, fly wheel, pumped-hydro). The RE technologies selected depend on one's geographical predisposition, resource availability, the end-use need, practicing conservation (behavioral change) to name a few considerations...

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