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Summer 2013 Blog - Troy Hodges

Troy Hodges is spending eleven weeks in Accra, Ghana working at Waste Enterprisers. 

August 17, 2013


Running a drying experiment with solar insolation with Kojo John Palfreyman.

People like closure. A bundled package of experience with a start and end: as the story goes, after his now-famous voyage aboard the HMS Beagle and years of scientific toiling, Darwin “discovers” evolution. Insert 99% of American romantic comedies: He/she gets the girl/guy. Off the silver screen and printed page, things hardly resolve so resolutely.  My last day as a Waste Enterprisers intern passed last Friday and while I have reached the end, my work hardly feels finished. Experiments still remain with inconclusive results. Answers continue to elude. Where’s my grand finale and moment of clarity I was promised by Hollywood?

Not every discovery we sought manifested itself by then end of my internship, but this ambiguity feels more real. The mission of waste recovery into fuel is bigger than my individual experience.  People dream of their big breakthrough be it in music, business, science, politics, etc.—a small piece of ever-lasting recognition. However, contributing towards a greater goal as part of a growing, moving collaboration—this is real self-preservation. I spent the last few days handing off my experimental data and procedure to other employees to run my experiments. My humble contributions live and breathe new life.

In the past few weeks, we concluded our last round of experimental runs to build our evaporation model for sludge drying as a property of sludge wetness. We introduced an element of surface “roughness” to our sludge samples this time to emulate real factory drying bed conditions at a large-scale operation and witnessed an unanticipated jump in variation in our results. As we are not only research scientists, but contributors towards an optimized fuel-making process, we eventually had to accept a certain level of error and declare our findings “good enough” to continue building our model for sludge drying. While our second round of experimental runs did not come out as cleanly as we hoped, it revealed many new insights into producing fuel—the ultimate goal, no?

Moving forward, we began running our next leg of experiments: sludge drying using sunlight. We took the tarps off and peeled off the film on our Plexiglas table covering and voilà! Our solar dryer is finally a solar dryer! We were reassured that out prototype greenhouse was working as we noticed huge spikes in evaporation on sunny days. At this point, we have gathered some reliable data on how evaporation rates change for different amounts of sunlight for sludge samples of varying wetness. However, analysing this data and parsing out the effect of the sun on drying from other factors such as temperature and humidity has proved trying. While unveiling these relationships still remains to be done, I feel content handing off the steering wheel to my colleagues and excited to hear about their further adventures in poop drying.

Equally important as my technical exploration of the sanitation and energy sector, I’ve had a first-hand chance to explore the policy side and power relations of these fields that exist in Ghana. Primed by my multidisciplinary background in environmental science and policy as a Conservation and Resource Studies major and organizing experience with the Fossil Free Cal campaign, I reached out to the Ghanaian Environmental Youth Movement (GYEM) after hearing news of a successful protest it led against a coal-fired power plant proposal to the Ministry of Energy. They welcomed me with open arms to collaborate on their Anti-Coal campaign and gave me a window of opportunity to learn about Ghanaian environmental practice and grassroots organizing. Learning the most effective ways to communicate environmental issues to audiences with a different cultural perspective of the environment than the US has been hugely insightful into what strategies a diverse global climate justice movement needs to employ to be effective.


Troy (on the far left) performing with “This House Is Not For Sale”, an afrobeat jam band in Accra.

Elsewhere, I’ve even seen my fascination with the energy sector permeate into new avenues—music! I was fortunate to link up with “This House Is Not For Sale”, an afrobeat jam band in Accra, and performed with them with my trumpet at a cultural center for a night of lively jams and good energy. We delivered an ode to the less-than-reliable Electricity Company of Ghana in the song “ECG” as our lead singer Kyekyeku told tales of missed soccer matches and dates gone wrong during blackouts, or “light off”. People howled with laughter as they identified with life with capricious electricity. Thanks for the inspiration ECG!

It is now lights off on my own Ghanaian experience, and while I cannot map out a climax or denouement, I couldn’t have asked for more in this unique chapter of my life. I’ll carry a lot of lessons back home to California with me, and in some small ways in the form of my research and personal relationships I see pieces of myself left in Ghana. So while I leave for the US, I also remain in Accra—making the ubiquitous Twi parting phrase quite fitting. Echina!Tomorrow!


July 16, 2013

Traffic. Just as surely as the sun will rise each day when summoned by the neighbourhood chickens, cars will stall idly in central Accra at mid-morning. While I empathize with these trapped passengers, I can’t help but feel grateful as I slide through rows of motionless cars on my daily bike ride to the work site. Cruising along Beach Rd towards the James Town site, I catch a glimpse of blackened waves contaminated from the nearby sewage dumping point into the ocean—a daily reminder of the problem Waste Enterprisers is working to solve.


Troy cutting metal for his project.

For the past month, I have been consumed in the scientific circle of life—hypothesizing, experimenting, failing, adapting, learning, hypothesizing…a beautifully frustrating and rewarding process. After finishing construction of our prototype sludge dryer, Kojo John and I began running a series of experiments to help build a predictive model of how sludge dries. Ultimately, this model can be used by Waste Enterprisers to predict how quickly fecal sludge will dry under varying weather conditions and allow them to best operate the fuel production process. The vision of a well-tuned large scale plant swims in all of our minds. The answers lie in the humble, oft-maligned sludge.

Initially, we set a small tray of fecal sludge at one end of the dryer with a fan blowing at a constant speed at the other end. For the span of an hour, we would measure the change in mass in real-time as water evaporates from the sludge, making sure to record temperature and relative humidity in the dryer. As sludge behaves differently depending on its initial water content, we ran this experiment at different starting total solid amounts (goopy and pungent to dry and earthy). However, after some fishy results with our stubbornly wild measuring scale, we decided to use a larger and shallower pan to minimize experimental error.


A tray of fecal sludge.

While some days at the sight require patience and attentiveness as the experiment runs its course, an adventure in damage control is never out of the realm of possibility. Ghana has little in terms of local industrial manufacturing, only surviving when not out-priced by cheap foreign imports. Accordingly, the majority of equipment and industrial products in Ghana are “fresh-type” Chinese goods—built for affordability and not much else. Broken drills and erratic generators are a normal occurrence, giving me the chance to  get some on-the-job training in mechanical and electrical troubleshooting by fearlessly prying open defunct equipment (putting it back together isn’t always as successful).


A solar dryer being unwrapped by Troy.

Fast forward, and our setup and experiment protocol has seen gradual adaption accrue into major changes—evolution in action. We built an addition extension onto our solar dryer  to prepare for larger-scale experiments and attempt to tame the pesky problem that is even airflow across the drying bed. Day by day, I am exposed to the trueness of “necessity is the mother of invention”. After a quick, dirty sketch of an addition that may or may not improve even airflow, I got to try my hand at some metal-working and build a crude air diffuser. Guess what—it works!

Looking forward, we look to finish building up the model, next factoring in the sun’s effect on drying and running full-scale tests to check the predictive power of our model. Of course, this is the plan. Along the way, there are sure to be just as many worthwhile delays, failures, and tinkering as predicted successes. Indeed, these missteps are the hidden gems of the research journey.


June 25, 2013

The Human-Energy Nexus: Putting People in the Energy Conversation

Energy access is seen as a lifeline of economic activity and rising standards of living. The Ghanaian government has prioritized universal electricity access by 2020 as one of its top goals. Amid rhetoric of large-scale energy projects, I went on the ground in Accra to talk to people about how energy affects their daily lives in part one of this two part blog series.

Let There Be Light

On any given night, one can see the flurry of lights and people that bare life to Kaneshie Market, a sprawling area of merchants and human activity. Even approaching midnight, piercing fluorescent and LED lights cast a glow of visibility on various goods ranging from shoes and used cell phones to vegetables, kebabs, and radio sets—a (hungry) scavenger’s playground.

On the pedestrian walkway over the freeway connecting two sections of the market, I notice a particularly illuminated and uniform section of light. I amble over to this bridge of movement and encounter around 40 women selling goods lining the edge of the walkway, each with their own ‘mini lamp’: a fluorescent light  mounted on a rechargeable dry cell battery.

I buy a Fanta knock-off from Yaya, a middle-aged woman in a colourful faux-Kente print dress selling a hodgepodge of sodas, antiseptics, and soap. A Kaneshie Market veteran, she’s occupied this same spot for the past 14 years. After an inquiry into the price of her lamp, she tells me she bought it for GH¢250 ($125). When fully charged, she says it provides 2 days of light. Yaya politely offers me a seat on a stool behind her repository to talk further and her friend nearby joins in the conversation, amused by this foreigner curious about lamps.

“What did you use for light before the lantern?” I ask.

“Ah. We use the street light, but now lights are off,” her friend answers as she motions toward the decrepit street light hovering above.


Battery-powered lamps dot a walkway with light at Kaneshie Market.

Yaya explains the Accra Metropolitan Assembly, the city government, shut off the street lights on the walkway five years ago and left the merchants to their own means to foster a lighting solution. Once a couple women on the walkway pitched the hefty sum for a mini lamp, the whole row of sellers followed suit and purchased identical lights.

I scale the staircase down to the base of the pedestrian walkway and inspect some mangoes under brilliant LED lights. Sarah, a mango and pineapple vendor, has an LED light with a rechargeable battery as well as a mini lamp. She claims she likes the LED light better, as it provides brighter light, lasts for 3 days when fully charged, and costs GH¢150 ($75)—out-performing the mini lamp on all fronts.

The ubiquitous sparkle of lights across the market is a testament to the growing popularity of off-grid lighting solutions. While these mini lamp and LED lighting models may be priced out of the range of those in energy poverty particularly in rural areas, they seem to be a working solution for merchants with sidewalk shop setups away from electrical connections. Mango in hand, I leave the bustle and dazzling lamps of Kaneshie as the market continues to hum late into the night.

On the Grid, But Not Out of the Woods

I recently met with Maxilikko, entrepreneurial owner of Maxilikko Ventures: a one-stop shop for cell phone airtime credit, accessories, mobile money, and more. Behind his salt and pepper beard sits a bemused smile as I chat with him about his business.

Maxilikko additionally offers cell phone battery charging services—GH¢0.50 ($0.25) will buy you two hours of charging time. Electricity in Accra is expensive, GH¢0.97/kWh ($0.49/kWh), and for those who can’t afford a regular utility service or to pay to electrify their homes where infrastructure is not provided, it is a costly amenity. Maxilikko lamented that he pays GH¢50 ($25) per month to power his small but electricity-intensive 6 ft by 6 ft store.

According to the Ghanaian Ministry of Energy, Accra is 96.8% electrified. Evidently the population of people living in electrified areas without the means to pay for electricity was squeezed out of this statistic. In his neighbourhood shop, Maxilikko gets 5-8 customers a day. During my short visit, two customers stop by with their cell phones to top off on extra minutes and recharge their batteries with a cedi or two.


For one half cedi ($0.25), one can charge their cell phone battery for two hours at Maxilikko Ventures.

However, when the power shuts down in Accra, Maxilikko’s business follows suit for the day. Electricity services commonly turn off for 8 hour periods 2-3 times per week. During heavy load shedding earlier in the year, blackouts would occur as often as 2 out of every 3 days for 10 hours at a time. As his livelihood is tied to electricity, he has considered purchasing a backup power generator, but it is “very expensive”. A generator can carry a price tag of GH¢500 ($250) and requires gasoline to run, currently priced at GH¢2.11/ L ($4.75/gal). A typical small 2kW generator consumes about 1.1 L every hour, meaning electricity then costs GH¢1.16 per kWh—even higher than pricey utility rates.

Other technology is enticing: Maxilikko is curious about a battery system with a charge controller as he is aware this setup is cheaper overall than a generator. Gasoline prices mandated by the National Petroleum Authority have jumped 20% since February and show no promise of dropping in the near future. However, he has yet to investigate where he can find a battery system—this option is not as widely available.

At the moment, Maxilikko will play his chances with utility electricity and hope against unannounced power load shedding: electrical Russian roulette. I leave my battery and a 50 pesewa coin in his hands to enjoy a phoneless few hours and fully charged battery, aware this novelty for me is others’ only option for energy access. The power is on and Maxilikko can run a fully functioning business—for now.


June 10, 2013


Trash flows from Korle Lagoon, the unofficial dumping site, into the ocean on rainy days.

As I stepped off the plane into the feverish humidity of Accra as passengers quickly rushed to secure a spot on the one undersized bus herding us to the airport terminal, I knew I was in for a swift change of lifestyle. While I can’t say I’ve fully adapted to the sweltering rainforest climate–rainy season showers have both helped and caught me completely off-guard in super-saturated wet garments—I have received a warm welcome from this bustling yet down-to-earth city in these two short weeks as a neophyte resident.

For the duration of the summer, I am working for Waste Enterprisers, a start-up waste-to-fuel company with big dreams, endless motivation, and a knack for handling feces. In Africa and Asia alone, 850 million people lack access to safe human-waste collection and treatment facilities.  Waste Enterprisers strives to bring an end to the sanitation problem in developing countries by harnessing the energy in sewage to produce biomass fuel and biodiesel. In Accra, one can easily spot the ghost facilities of wastewater treatment plants shut down after depleted funds. In place of this comes an economically feasible, sustainable business—GreenHeat fuel! The sewage is redirected from the notorious dumping sight “Lavender Hill” (ironically named for its tender fragrance) that feeds directly into the ocean, and the fuel itself replaces burning fossil fuels. Additionally, its ash serves as an input into industrial processes such as cement production.


Navigating the timber market for supplies.

Based at their biomass fuel production sight in Accra, I am interning as a Process Engineer to conduct research on fecal sludge drying—more fun (and odorous) than paint drying, I promise. Building on these findings, I am part of a team designing a novel sludge solar dryer that harnesses the sun’s energy to turn liquid sludge into a dry, combustible fuel while minimizing electricity use. Working closely with Kojo John Palfreyman, my Cal Energy Corps buddy in Accra also with Waste Enterprisers, we have constructed a prototype solar dryer to begin running experiments on this coming week. While I was able to pull from my environmental science background for designing the upcoming experiments, I have received a crash course in woodworking, construction, and supply chain management. Sourcing materials in Accra is not as simple as driving to your nearest Home Depot or placing an order on Amazon. Oh, no. For our various solar dryer and experiment materials, we have ventured to Galloway—a sprawling Mecca of mechanics, forgotten metals and electronics, and imagination. Like Sid’s army of piecemeal Frankenstein toys in Toy Story, here new machines are reborn from the scrap metal of old cars and other long-useless products. From our wanderings, we tracked down a West German centrifugal fan (yes, made when West Germany existed), various fasteners and brackets, and bargained for wood at the nearby timber market. At first daunting and seemingly utterly chaotic, it was fascinating to see how largely efficient the markets could be once you know your way around.


Piecing together the beta solar dryer.

This week begins the commencement of our first solar drying trials on the prototype dryer. On top of the learning I expect to obtain from a week of testing, I have been getting constant lessons with all my senses as I sponge up Ghanaian culture and customs. From learning azonto dance to eating fufu and groundnut soup (never chew your fufu!) to absorbing Twi phrases, the growing experience doesn’t stop at the end of the workday—it only just begins.

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