Boat diesel generators seem to incite much debate and discussion. Are they worth the effort? Are they good value for money? Some also ask whether its generator vs inverter as a decision for having boat electricity. Many bemoan the fact they require maintenance, or they have too much weight and are unreliable. The fact is that most boat diesel manufacturers have innovated over the years along with technical advances. They have significantly reduced weight, and also the physical size. Noise emissions have drastically reduced and also the vibration levels. The argument that your diesel generator is keeping the anchorage awake is also no longer viable. There is much to consider about boat diesel generators.
So we start with the first big question, and that is why do you want to install a boat diesel generator? It is an important one to ask as a decision to install one is expensive and adds weight to your sailboat. For the purposes of this discussion we will assume we are looking at a 40-45 yacht for this installation. Important boat diesel generator selection factors. Anything under that starts getting a challenge for space and weight, and anything above isn’t an issue in most cases. Many couch the argument as one of an inverter and more batteries vs a generator but there are important differences. Many also weigh up renewables and more batteries with an inverter but that equation has its limitations as well. There are some great small boat generator options on the market.
The first answer is as a replacement charging source for my batteries. Running my 30 hp diesel for a few hours daily to recharge my house batteries is uneconomic. A high output alternator might load up the main engine with about a horsepower or so at peak load. Then we might get some heating of water through my calorifier if it gets warm enough. I have helped install engine driven eutectic refrigeration compressors which also might add another horsepower or two. So now we have my diesel engine clattering away on low load, which is costing money in fuel and also maintenance as diesels do not like being run at light loads. The cylinders get glazed up and injectors get fouled and so it goes on. I hear many who cite not having a generator because it is extra maintenance, but an oil change every 6 months? Really! Some I have met also are fixated on the possibility it might fail. Check out boat generator installation information.
Back to the question about why? Many folk say its because they want to run air conditioning. But given they run it only very occasionally I am not sure all that expense and weight of the AC and the genset is not economical sensible, but that’s just me, just saying! I want to run my genset to recharge batteries via a good battery charger. I am happy to add the extra resistive load of the hot water heater as well. What else? well while AC power is on, I am also charging my various devices, but I also prefer to do that through a small inverter as well.
There are many boat diesel generator manufacturer options that include Fischer Panda Generators, Onan Generators, Northern Lights, Mase Generators and Kohler Generators. I will cover some of their innovative solutions. I would be happy to have any of them on my boat.
Maybe if cooking and you use a microwave or a food processor at the same time. Many go on about the hair dryer and so it’s a good time to be showering and hair drying at the same time. This also leads into watermakers, some have AC powered units and running them with the genset is also a possible load. I have yet to see someone running dishwashers and washing machines on a 40 foot boat but some do I am sure. Some do run AC powered electric eutectic refrigeration and freezer which is a good reason. I do know some folk who also run dive compressors. Electric water kettles really pull some power as do toasters and as a primary reason I am not so sure. Lastly some also run their coffee makers, for many indispensable but I use a stove top Moka pot percolator. Once I was asked about using a clothes iron, does anyone iron on a cruising yacht I wondered. I have also yet to see anyone running an electric stove on a smaller cruising yacht but perhaps someone is using some inductive hob somewhere from a small genset. So for me I would look at a small boat diesel generator, say around 5 kW, which would cover all my needs. Look at power consumption issues about the boat generator here.
If you maintain your boat diesel generator properly you should not have to many issues to worry about. But if your boat generator won t start then look at these solutions. If you layup during the winter then you should know how to winterize boat generator properly. Choose your boat diesel generator carefully.