Author Archives: Joan Richmond-Hall

We’re filling the tanks and on our way!

This brief diary chronicles our first three days of adding manure to the digester. You’ll see that some days were certainly more successful than others but our team valiantly struggled against our most recent cold snap. Start at the bottom and work your way up;I hope to have more updates later this week. I hope to post more updates later this week.

Monday, 27 January 2014
Today was colder than expected and we woke up falling snow. Snowfall wasn’t heavy, but the winds were very stiff. The Townsends brought a pump to the Osha farm and ice cover doesn’t appear to be a problem there. Today, road conditions prevented us from moving manure from either farm.
We’re going to wait until the weather improves on Thursday and try to run through the weekend if necessary. Our first week of operations is already a teaching experience. Planning for successful winter care and feeding is certainly a priority.

Sunday, 26 January 2014
Early this morning – 2 am – the wind rose tremendously and brought the polar vortex screaming back into Central Vermont with a vengeance, dropping temperatures well below zero F. This morning donned bright, windy and cold with 1F at 9 am. We got two loads of manure into the reception pit, and with the hydrolyzer at about 85% full, we moved to open the valve to the larger AD tank. The cold air had frozen the valve closed. We stopped trucking manure for the day  and used a propane heater to get the frost out of the valves and outdoor piping. By the end of the day we were able to pump manure from the hydrolyzer tank to the large AD tank, and we’d worked out some bugs in reception pit pumping and valves. The temperature struggled to rise out of the single digits and wind chill made it feel much colder.

Frozen valves

Frozen valves

The weather is due to warm up tomorrow and we’re hopeful that we can get back on track. We’ll be hiring and excavator and agitator pump so that we can get back into the Osha pit. As the temperatures are forecast to plummet again on Tuesday we’ll have to make tomorrow count!

Saturday, 25 January 2014
At long last, we begin loading VTCAD with dairy manure. After years of planning and months of construction we’d hoped to start yesterday. However, single-digit temperatures prevented us from starting a the tractor needed to agitate and pump manure from the Osha farm pit. The heroic efforts of Charlie Dana, Aaron Townsend, Jason Lambert and the farm crew got the tractor running by late afternoon and they ran it all night to ensure that we’d be able to start today.

Charlie nurses the tractor back to life.

Charlie nurses the tractor back to life.

Then the weather took over. The agitator pump at the Osha pit was overworked in the cold and stopped working; we think the gearbox will need to be replaced. So by 10:30 we had three truckloads added but work came to a halt. Thankfully, VTCAD will be fed from two farms. Work shifted to the college farmstead. Pickett came down and managed to start the excavator that they had used to build our new effluent pond. They managed to use the arm to pry the machine out of the ice. Charlie Dana got the farm tractor and agitator pump started. They broke through the ice on the pit and we started receiving manure from the college pit. By 3 pm we had 12 truckloads and they are still coming. Interestingly, when the pumps go on we think we can hear the sand moving through.. could be ice! We finished the day about 4:30 pm with 20 truckloads of manure, about 80,000 gallons that brought the hydrolyzer to about ¾ full.

Joan, Francois and Mary

Joan, Francois and Mary

Visit from Vietnam’s Agricultural TV (3NTV)

On Monday 14 October, a group of four reporters and camera folks from an Agricultural TV network in Vietnam came to visit the VTCAD project. They were in the US for a three week tour of interesting agricultural projects and we were lucky enough to be included on their itinerary. I gave them an introduction, they filmed some segments about the college and the project, and then we took the tour.

I learned a bit about AD in Vietnam during their visit. Apparently many farms, large and small, use anaerobic digestion to produce biogas. However, they use biogas very differently than we do. In rural Vietnam, biogas is used as a cooking fuel rather than a means of producing electricity. If you consider Vietnam’s rural climate, their more direct use of biogas and the fact that scrubbing and generating engines are not required its clear that they can apply the technology with less expense than we can here in snowy Vermont.

Thanks to Xuan Bui Thi and her crew for their visit. We appreciated the chance to meet them an to learn about a little about AD in Vietnam.

Women Can Do visits our mechanical cow

Women Can Do, 17 October 2013
This morning about a dozen girls and a couple of teachers visited our construction site as part of Vermont Works for Women‘s annual Women Can Do day at Vermont Tech. I gave them a brief introduction to the project, we pawed through a trashcan to identify organic waste and then we met Francois for the tour. Now that the two digestion tanks are spun up and completed we got to go inside and then see how the tanks are made by watching our final digestate tank under construction.

Great group of students and a beautiful day. One of those days that my job is sheer pleasure!

– Joan Richmond-Hall

Will Act 148 help Cow Power expand?

In the Sunday 21 July issue of the Times Argus, Sandra Levine, a senior attorney at the Conservation Law Foundation in Montpelier wrote an article praising Green Mountain Power’s Cow Power program. She touted the program’s successes:

  • 12 dairy farms producing ….
  • Power for 3000 homes;
  • While decreasing atmospheric carbon dioxide by 40,000 metric tons.

Ms. Levine believes that anaerobic digestion has a great future in Vermont because it supports agriculture and mitigates greenhouse gas pollution while producing renewable energy around the clock.

However, she notes that expansion of Cow Power faces a number of challenges. The technology is expensive – too expensive for small farms with limited herd size and manure production. Ms. Levine sees the connection between anaerobic digestion and Act 148. Farms could provide a destination for the organics we will soon be prohibited from landfilling. If farm anaerobic digesters are allowed to accept more than 49% non-farm organics and to accept the post-consumer residuals generated in our schools, cafeterias, restaurants and homes, farmers could harvest the energy and recycle the nutrients for crops.

We agree! And we believe that our AD project will show how small farms and their communities can make the best use of technology’s co-products: heat; nutrients and carbon dioxide. Because our AD is located next to the college’s central heating plant we can capture ‘waste’ heat and reduce our enormous use of fuel oil. Our Landscape Development and Sustainable Horticulture program would love to pipe exhaust carbon dioxide into a greenhouse in order to increase the rate of plant growth!

Ms. Levine worries that digestion of organic residuals will produce lots of nutrients. She worries that these nutrients could end up in our streams, rivers and lakes producing problems like those seen in Lake Champlain today. We believe that community or regional nutrient management could provide a solution. We are working with a group of eight Randolph farms that may benefit from the project by using digester nutrients in place of commercial fertilizer. The amount of land that can be served by the project will depend on the nature and chemical makeup of the food residuals that power the project. But we’re starting by collecting field, soil and crop data and creating nutrient management plans with our farm partners. Along the way we’ll be monitoring soil and water quality to demonstrate both the environmental and economic benefits of using AD to recycle, if not upcycle, ‘waste’ nutrients.

– Joan Richmond-Hall, Ph.D.