Shannon and I have lived onboard Nymeria for over five years now. Much of that time was spent tied up and plugged in at a marina. Since arriving in the Florida Keys over a month ago, we’ve spent nearly all of it on a mooring ball. For as much time as I spent studying and optimizing my power usage, being entirely self-sufficient for three weeks proved to be a challenge.
Despite our solar panels producing a significant amount of power, we quickly realized that it wasn’t quite enough. During the equinox, we were consuming an average of 3.5-4 Kwh per day, which was not fully met by our solar panels even on a sunny day. Although our panels would generate approximately 3.6 Kwh on a perfectly sunny day, the average daily output was only about 3Kwh, leaving a deficit of 500-1000wh. This highlighted the importance of our generator, which we relied on to make up the difference.
When we installed the new engine, we ensured it included a high-output alternator and a safe charging mechanism for the house lithium batteries. However, at maximum output, the alternator barely outpaced the solar panels, and it added hours of low load run time to the main engine, making it a backup power source unless we were underway.
For the first time, we were forced to rely heavily on the NextGen 3.5Kw diesel generator that was installed when we bought the boat. Although we had run it periodically for testing and basic maintenance, we had never run it at full load for extended periods. It seemed to run hot, but we weren’t overly concerned. However, when we purchased a “spares” kit, it included new sensors, including a high-temperature cutoff. During an extensive overhaul, we installed the new temperature cutoff and discovered that the generator was, in-fact, running hot and shutting itself down after only 15 minutes under load. Over the course of two weeks, we spent several hours each day testing, replacing, and fixing various parts of the raw water system, pumps, impellers, passive coolant system, heat exchanger, and exhaust system. While each step improved the situation somewhat, the generator still overheated after 20 minutes of moderate load, making it insufficient to run the watermaker or charge the batteries efficiently.
One of the NextGen techs advised me, “As long as you’re still doing ‘maintenance’ items on an old unknown engine, there is hope.” Even with that advice, the next steps seemed to be replacing parts and hoping, and after calculating the cost of the next steps, we opted to purchase a new Honda 2200w portable generator, a cruiser’s workhorse that would better suit our needs. Although we had invested about $900 in parts and 20-30 hours of manual labor into the existing generator, it never achieved a trustworthy state, and the next part would have cost several hundred dollars. Furthermore, removing the old generator would free up a massive area of storage for the new generator as well as the watermaker.
It was tough to give up on the old generator, but we had given it a fair chance. The new Honda generator should last for many years and will not require an unknown amount of continuous work to achieve a reliable state.
Doesn’t this mean you need to keep significant gasoline on hand? While the outboard for the dingy burns gas the Honda generator will burn significantly more. Are there small, portable generators that burn diesel? Ours burns gas or propane – we keep propane due to its shelf-life.
Yes, that is a major concern. We already have a 6 gallon gasoline tank for the dinghy, we will probably get a 3-5 gallon spare to store along with our extra diesel. The Honda generator has a ~1 gallon tank and at high power states 3+ hours of runtime on that. ~.3gal per hour. Main engine burns ~.4gal of diesel per hour for charging purposes. I need ~2-3 hours of runtime every few days. So I’m estimating about 3 gallons a week.
I think we already had the smallest/cheapest diesel generator available, and it’s at least $8k to replace. I’m still torn up about the decision to get rid of it.