23 January 2012
If you have been a long time blog follower, you’re likely fatigued with my recounting the challenges of trying to keep Sea Sharp with enough power to satisfy our needs on long term cruising. I’ll take another tack and liken energy management on a modest cruising boat to personal weight management.
Most of us struggle with trying to stay trim and svelte as we get older, particularly as we enjoy the good things in life. Notwithstanding the miracle diets, exercise regimes and lose weight effortlessly ploys, we know that it really is a simple equation.: energy in vs. energy out. In a human context, if you consume more calories than you burn, you’re going to put on weight. In a boating context, if you consume more energy than you restore, you’re going to deplete your energy source (batteries).
So, while we had solar panels, larger battery banks, higher capacity alternator, wind generator, etc, we found that we were always in a deficient situation with waning battery power. This resulted in us having to run our main engine which is neither efficient nor good for a diesel engine to operate without a good load.
Over the past summer I sought out the advice of several people whose opinions and expertise I respect, notably Norman an Mike and with their help came up with an action plan and project list for this commissioning season.
First order of business was to understand better my usage and energy restoration profile. So, this means an intelligent battery monitor. This device is much more intuitive than the simple ammeter and voltmeter that I had on sea Sharp. This allows you to understand what is taking the energy, how quickly, what’s left, how rapidly it is being restored, and simply, to get a handle on what’s going in and coming out. It changes nothing materially but lets you know what’s what. So, I purchased and installed a Victon monitor, somewhat complicated to install but very informative and revealing in terms of management
Next was to determine the state of health of my existing batteries. I have five batteries in two banks, They are relatively inexpensive lead acid batteries. I was suspect that they might have been “cooked” as a result of over use in the past two years since I installed them and was prepared to acquire new batteries. This exercise alone is a very complex situation to analyze as there are various battery types, voltages, sizes, configuration, etc. Fortunately, I had my batteries analyzed and they checked out fine.
As I mentioned previously, I already had two solar panels. I decided to install a third. Solar is a bit expensive but quiet, reliable and, of course green. And with the installation of the davit system I had done last year, I have a large platform to put them. So I purchased, and with Roger’s help, installed a third, 100 watt panel bringing my total solar to 260 watts.
I installed a “smart charger” to replace the stock “dumb” charger which came with the boat. Without getting into a lot of details, this charger which uses 110 volt current, either from being plugged into “shore power” or powered by my gasoline generator, charges the batteries quickly and effectively.
I opted not to change the alternator on the diesel engine as I had just upgraded two years ago to a high capacity alternator.
Finally, I replaced a number of lights, formerly incandescent and fluorescent, with Light Emitting Diode (LED) lights. These are quite expensive but provide an equivalent amount of light as the older bulbs at 10 % of their amperage draw. This is significant in terms of overall consumption.
So I’m happy to report that while we still have to be parsimonious with our use of electricity, we are making good progress and with sunny days and a bit of wind, can keep up without having to start the main engine.
Thanks Norman and Mike and others for your advice! Now if I could conquer my weight management challenges (cruising life with less exercise than normal is slowly taking its toll).