By Doug Reynolds
Executive Director, NOTO
n the last issue of The Outfitter, I took an example of a hypothetical lodge that was operating on a 20 kilowatt diesel generator and did some basic number crunching to see how much money could be saved with a fairly basic renewable energy installation and what the payback time might be. Right after the issue went out, I got a call from Joe Ott of French River Lodge. Joe had just read the article, and called to say that my calculations seemed to be pretty close. Joe had just installed a system at his lodge and it turned out that his installation was pretty close to the one I imagined in my article. I called Joe back recently to get an update on how things had worked out now that he was through the better part of a season with his new, renewable energy installation.
Joe told me that he had two main objectives in mind when he went into this project. The first, of course, was to save money on diesel fuel. His second objective was to go from 17 hours per day to full time power, and to have well regulated, power-line quality electricity for the modern electronic devices that are everywhere these days. With this in mind, he started his search by researching the power inverters that would be the heart of his system.
Joe settled on the German made Sunny Boy and Sunny Island inverters because of their features and high quality true sine wave output. The importance of true sine wave output has been underscored for me in the past by system engineers. Lower cost inverters that produce a modified sine wave or modified square wave output (both terms mean the same thing), may significantly shorten the life of sensitive devices like refrigeration compressors.
The system uses one Sunny Boy DC to AC inverter and four 5 kilowatt Sunny Island battery inverters stacked to give 110/220 volt output just like his generator. Because they are stackable, he can add pairs of inverters (they need to be added in pairs to get 110/220 output) any time in the future to increase capacity. No transformers are required as the Sunny Island master controls all aspects of the system.
The inverters also act as battery chargers and switch over to that function as soon as the generator is brought online. They also include battery monitoring and control circuitry for automatic generator start up, if desired. Joe told me that he prefers to start the generator manually, but uses the monitoring function to determine when he needs to use the generator to top up the batteries.
When the generator is started, the inverters distribute the load so that the generator is loaded to 80% of rated capacity for optimum efficiency.
Like any renewable energy system, Joe’s system has a large battery bank, operating as a 48 volt system. Unlike a system that is designed to carry the load over several days of overcast weather, this battery bank is more modest in size and assumes that the generator will run for some period of time daily to keep batteries topped up. The renewable energy portion of the installation consists of a bank of 18 solar panels, each rated at 160 watts. There is also a wind turbine rated at 2.8 kilowatts in a 15 mph wind. Joe told me that the wind turbine is the one part of the system that has been a disappointment. It was relatively expensive and difficult to install, and rarely produces much more than a kilowatt. If he had it to do over, Joe told me he would have invested the money in more solar. For a year round operator or a site with better wind, the situation might be different.
So how has it all worked out so far? Joe is absolutely delighted. He has gone from 17 hour to 24 hour power, and cut his generator run time by 10 hours per day. This translates into a fuel saving of about 35 litres per day or $40 to $50 per day at current fuel prices. He will also see greatly reduced generator maintenance, and the noise is greatly reduced. He told me that his guests are intrigued by the system, and impressed by both the reduction in generator noise and the green technology.
What did this all cost? The basic system with the wind turbine installation came in at $112,000 with an additional $8,000 of extra cost for the raising of the wind tower and additional wiring. The funding submission to Northern Ontario Heritage Fund was based on an estimated cost of $100,000 and Joe received 50% of this estimated cost. Joe indicated that when estimating the cost of the system it would be wise to include an additional $10,000 or so to cover the cost of incidentals such as framing materials, fastening hardware, wiring, etc.
Joe had nothing but praise for the support he received from Ministry of Northern Development and Mines and NOHFC staff. He told me that the application process was very quick and straightforward and that he received excellent support from program staff.
In the end, I must admit that I was a bit surprised how close Joe’s experience came to what I predicted when I modeled the hypothetical system in the last issue of The Outfitter. With the quality of current technology, the funding support available and the price of fuel, a renewable energy installation really does make sense for an off-grid lodge. Rising fuel costs and falling prices for solar panels and other equipment will only make it even better as we move forward.
This article was taken from pages 11 & 12 of NOTO's "The Outfitter" publication, Fall 2008 Issue