Maine Huts & Trails Sustainable Energy and Waste Systems

As summer is winding down and our research is coming to an end, we would like to share what we have been doing since our last post. We have spent most of our time gathering data on the huts’ electricity production and usage to see how well their solar power systems are working. We have been entering our data into a modeling system called SAM, which was developed by the National Renewable Energy Lab in Colorado. SAM uses detailed weather data and solar panel performance statistics to model energy losses and predict annual energy production. It also creates financial models, which we have been using to optimize Maine Huts & Trails’ energy savings and calculate returns on potential investments.

The solar panels of Flagstaff Hut, 9 panels on the roof and 18 panels mounted on a pole.

Storage is key to the success of any off-grid solar power system, and investing in storage can have a considerable impact on efficiency. Off-grid systems rely on batteries and backup generators to make it through cloudy weeks and do not allow for the sale of excess solar energy. This means that whenever the battery bank fills up, the solar panels give off excess energy in the form of heat, and all the energy that is not required to meet the electrical load is wasted. Our models show that Maine Huts & Trails could store more solar energy and spend less on propane if it invested in much larger battery banks for each of its off-grid huts. By increasing the storage capacity of the huts, the organization would decrease its generator usage and rely less heavily on propane for power. When we doubled Flagstaff’s battery bank in SAM, its estimated propane spending decreased dramatically because there would be more battery capacity to harvest solar energy. Adding more solar panels in addition to doubling the battery bank showed an even greater impact with higher energy production and less dependence on the generator.

Earlier in July, we had a meeting with Calen Colby, a board member of Maine Huts & Trails and co-owner of Colby Engineering, to present our preliminary findings while we were still working our way toward these conclusions. In preparation for our meeting, we compiled our research into a document for Mr. Colby to read over. We also created a schematic of the energy flow for Flagstaff Hut to confirm our understanding of how the systems work together. It was a pleasure to talk to Mr. Colby about our research and to listen to his ideas about future projects for the huts as well as the feedback he had on our conclusions. It was clear that he is passionate about Maine Huts & Trails and sustainable energy through his company’s efforts to repair the hydropower system at Poplar Hut and his ideas about adding wind power to Flagstaff Hut. It was helpful to hear his thoughts on the sizing of the generators at the huts, which is a source of some inefficiency and translates to increased spending on propane and solar energy waste. He explained that the organization decided to invest in generators that can work at high wattages because these generators last longer.

This past weekend, we had the opportunity to talk about our research for a second time at the Colby Undergraduate Summer Research Retreat (CUSRR) in The Forks. We also listened to our fellow summer researchers speak about their projects and went white-water rafting down the Kennebec River. Overall, CUSSR was a great experience for us as we were able to share our work with others and prepare for our upcoming presentation to the Maine Huts & Trails board members this week.

For our meeting with the board members, we have compiled a list of potential investments Maine Huts & Trails could look into to improve the current energy systems. These include purchasing more batteries to increase the battery capacity and having additional staff training on how the systems work. This summer has been very informational and educational to us and Maine Huts & Trails. If we had some more time to continue our research, we would install current clamps to obtain more accurate electrical load data, look into Mr. Colby’s idea of investing in wind power at Flagstaff Hut, and investigate the possibility of using programmable logic controllers to efficiently control the photovoltaic and generator systems.

At the beginning of the summer, our knowledge of sustainable energy and waste systems was limited to the basics of solar power. After ten weeks of working with 

Hiking on the well-kept trails to Flagstaff Hut!

Maine Huts & Trails, we have gained valuable knowledge about sustainable energy systems and its applicability to residential homes. We have realized while that it is important to have sustainable energy systems,  it makes an even greater impact to have compatible and effective configurations that actually make use of the sustainable technology. Learning about these systems is important because it helps us to think of ways we can reduce our carbon footprint and promote sustainability in the future. We have enjoyed our time working with Maine Huts & Trails and cannot wait to visit the huts again in the future!

-Sarah and William

An Overnight Stay at Flagstaff Hut

After multiple day visits to Flagstaff, I wanted to have the full experience of staying overnight, so I booked a trip for the last weekend of July. Staying overnight at Flagstaff Hut was definitely a highlight of my summer as it was filled with breathtaking nature scenery and unexpected experiences. My adventure began by seeing a moose (!) on the road about a thousand feet away as I was turning onto the trailhead. Upon arriving at the hut after a hike along the lake, I was greeted by hut staff James and Erin who helped to check me in for my overnight stay. After settling into the spacious room that I had to myself, I decided to go kayaking. With no particular destination in mind, I kayaked across Flagstaff Lake and admired the stunning mountain backdrop that enveloped the lakeside. It was the perfect day to be out on the lake with the sun shining through the clouds and minimal wind to push me around. I eventually stumbled upon an island near the dam and stopped there to read my book for a couple of hours, situating myself on a rock by the shore to soak in the sunlight. After a few hours of exploring the island and kayaking around, I made my way back to the dock to see a few other families enjoying the lake. Eventually, dinner rolled around, and I was fortunate enough to meet a few of the parents I had seen earlier while enjoying some delicious homemade and locally sourced food. As nightfall came, I joined the hut staff in swimming under the stars and saw my first shooting star! It was a surreal experience because it was like swimming in space as I looked up to the sky with the serenity of Flagstaff Lake at night. Before going to bed, we relaxed outside around a campfire to watch some more shooting stars soar across the night sky. After a long day filled with many adventures, I retired to my cabin and quickly fell asleep. In the morning, I enjoyed a scrumptious breakfast (the blueberry muffins were the best!) with the parents I had met the evening before and packed up my belongings into my backpack. I said my goodbyes to the staff after breakfast and headed down the lakeside trail to begin my way back to campus. When I had the idea of staying at Flagstaff, I was only planning on going kayaking around the lake, but I left the weekend with some memorable experiences and newfound friends.


My view from the island where I read my book!


Maine Huts & Trails Sustainable Energy and Waste Systems

Hello, my name is William Thao, and I am studying Environmental Policy at Colby. At Colby, I am a member of the Mock Trial team and participate in a couple of environmental clubs. I am from Minnesota, so I am excited to be spending the summer in Maine!

Enjoying the view from the Vista!

My name is Sarah Bash, and I am going into my junior year at Colby. I am a physics and philosophy double major from Bethesda, Maryland. On campus, I am a member of the woodsmen team and multi-faith council, and I am excited to join hall staff as one of the community advisors this coming fall.

We are the sustainable energy interns working with Maine Huts & Trails this summer through the academic partnership with Colby College. Our objective is to analyze the energy and waste systems at Maine Huts & Trails, which include wood gasification boilers, solar panels, and composting toilets. So far, we have been deepening our understanding of how these systems work and using data we have gathered to calculate their respective efficiencies. With this data, we hope to make recommendations to Maine Huts & Trails for possible investments in potentially more efficient or sustainable options. In the past few weeks, we have visited Poplar Hut, Flagstaff Hut, and Stratton Brook Hut to get a first-hand look at the systems.

At the beginning of the summer, we traveled to Poplar Hut with Professor Whitney King, our supervisor at Colby, and Merrie Woodworth, the Youth and Educational Programs Coordinator at Maine Huts & Trails. We were lucky to squeeze in a visit before the hut closed for the summer. We began our walk to the hut by crossing the Poplar Stream as it raged into a small pond, and we continued onto the service road where we ran into Poplar Hut’s kind caretaker. He accompanied us to the hut, where we looked at the sustainable energy and waste systems. Like all the other huts, Poplar Hut is heated by a wood gasification boiler connected to a radiant floor heating system, which produces significantly fewer emissions than a standard wood stove. For electrical power, solar panels provide solar energy to the off-grid hut. We also got to see the composting toilets for the first time, which use a special lubricating foam instead of water. These toilets are more sanitary than standard flush toilets because the composting process separates liquid and solid waste into components that no longer carry human pathogens. The composting tubs below the toilets have a highly effective drainage system, which helps keep the compost clean and dry. Added bacteria, fungi, and earthworms promote aerobic decomposition in the tubs, further decreasing the volume of the waste produced. Each hut only accumulates about fifty gallons of compost every four or five years. After walking through the hut, we learned a bit about Poplar Hut’s hydroelectric system that is currently under repair. We walked to the nearby dam that powers it and looked at some of its components. While familiarizing ourselves with the Bigelow Preserve after our visit, we saw a moose munching some of the vegetation on the side of the road! We got out of the car, and stood in the street for a while, admiring its overwhelming beauty. It was the first wild moose either of us had ever seen.

View from Flagstaff Lake

Next, we visited Flagstaff Hut during staff training, which gave Merrie the opportunity to introduce us to the entire hut crew as well as a few of the year-round staff. The atmosphere was energizing, and we had a lovely time meeting the passionate and knowledgeable members of the Maine Huts & Trails staff. It was evident that everyone there cares deeply about the Maine Huts & Trails mission. We had a great conversation with John Winter, the Huts Manager, during which he shared invaluable information about Flagstaff Hut’s solar power system, describing how and why it has changed over the years. Flagstaff Hut has twenty-seven solar panels, which power the electrical load of the hut. When solar energy cannot meet the demand of the electrical load, a propane generator turns on to provide additional energy. This generator is used in the summer to provide hot water for showers and domestic use. Flagstaff Hut also uses a wood gasification boiler and composting toilet system. Flagstaff Hut is perfectly nestled in the Maine woods by the lake, which provides a relaxing atmosphere in the outdoors. Before we left, we walked to the shore and admired the Canadian mountains across the lake as Merrie told us the story of Benedict Arnold sailing through Flagstaff Lake in 1775 to conquer Quebec City.

Heading into the mountains from the Airport Trailhead

This week, we hiked on the trails to Stratton Brook Hut. Our adventure began in the vast field of the Airport Trailhead with an open view of the Bigelow Mountain Range. During our hike, we saw Sugarloaf Mountain from Crommet’s Overlook and many vibrant wildflowers along the trails. The pleasant breeze and shade from the tree cover made it easy to maintain a chipper outlook throughout our long and beautiful hike. We caught the occasional tick scuttling up our pants, and thankfully none found a home on our bodies. As we entered Stratton Brook Hut, we were greeted by Aaron, a member of the hut crew, and chatted with him about our hike as we devoured our lunches. He showed us the energy and waste systems in the basement and pointed out where we could see the solar panels on the roof. Unique to Stratton Brook Hut, there are three solar panels solely for solar hot water in addition to thirty-three solar panels for electricity. While this hut is connected to Central Maine Power, the solar panels generate enough electricity to feed additional power back into the grid. For waste and heating, Stratton Brook Hut has the same systems as the other huts, a composting toilet system, and wood gasification boiler. As the afternoon arrived with some slight rain, we said our goodbyes to Aaron and departed from the hut. Before leaving the mountain, we visited the Vista and admired the beautiful view of the mountains.

We have enjoyed visiting the huts and learning more about sustainable energy and waste systems. We look forward to continuing our research and helping Maine Huts & Trails with their sustainable systems.

-William and Sarah