Last year the Common Ground Fair in Unity had these workshops in their 'Energy & Shelter Speakers' Tent.
Friday: 09:00 - 10:00 Practical Tips for Accessible Living
10:00 - 11:00 Solar Water Heating Basics
11:00 - 12:00 Efficiency: The Cheapest Energy You Can Buy
12:00 - 1:00 Microhydro for Stream & Tidal Current
1:00 - 2:00 Solar Hot Water Systems: Basic Fundamentals
2:00 - 3:00 Solar Hot Water Works Great in Maine
3:00 - 4:00 Save Money & The Environment - Feel the Difference
4:00 - 5:00 Maine Made Wood Pellets Q&A
Saturday: 09:00 - 10:00 Monolithic Heated Slab Foundations
10:00 - 11:00 Masonry Heaters in Maine Homes
11:00 - 12:00 The Small House Sketch Book
12:00 - 1:00 Solar Power That Makes Cents for Your Home
1:00 - 2:00 Green Building & Passive Haus
2:00 - 3:00 Small Anaerobic Digesters for Small Dairy Farms
3:00 - 4:00 Solar Water Heating Basics
Sunday: 09:00 - 10:00 Efficiency: The Cheapest Energy You Can Buy
10:00 - 11:00 Change Your Space, Change Your Life
11:00 - 12:00 Masonry Heaters in Maine Homes
12:00 - 1:00 Monolithic Heated Slab Foundations
1:00 - 2:00 Solar Hot Water Works Great in Maine
2:00 - 3:00 The Small House Sketch Book
3:00 - 4:00 Save Money & The Environment - Feel the Difference
On their website, you can find this list of topics.
Maine Organic Farmers and Gardeners Association > The Fair > Schedule of Events
You can also access who the speakers were and in many cases what companies they work for and their credentials.
The topics change every year, as do the speakers.
The Common Ground Fair is hosted by MOFGA in Unity.
Maine Organic Farmers and Gardeners Association
It focuses largely on off-grid, sustainable, organic farmers; and it gets 18,000 to 25,000 people each day at the fair.
The fair has 63 different venues [workshop locations / pavilions], each venue has it's own topic of workshops.
The 'Energy & Shelter Speakers' tent schedule is what I posted above. Each of the 63 different has their own full-day schedule of workshops for the off-grid, sustainable, organic farm type.
I attend every year.