I  place generators in the same class of boating equipment as autopilots. Most boats I've owned over the years (a large and still growing number) had neither piece of equipment, and in my uninformed bliss I never missed them. But after finally getting one of each, I find I can't live without them. If I'm driving straight for more than, say, 100 yards, the autopilot is on, and if I'm on the boat away from shore power, you can bet the generator is running.

Many skippers feel the same way, and a generator is now considered a standard and necessary piece of equipment on most inboard boats. Even many outboard boat companies, which never offered gensets until a few years back, now make them available as optional equipment; a few companies even make them standard. The lure of air conditioning and real refrigeration is just too hard to resist.

Many inboard boat companies also add complex electrical systems that require more and more AC power, so we're seeing larger and more powerful gensets in boats and even multiple units for truly complex demands. Systems like watermakers, ice machines, extensive lighting, multiple hot water heaters, fully equipped galleys, and powerful entertainment and communication systems all need juice, and the demand for amperage continues to rise dramatically.

Although generators have grown steadily in size and power to meet the growing demands of modern boats, they haven't changed much from a technological point of view until very recently. They all convert mechanical energy into electrical energy by moving a coil of copper wire through a magnetic field, thereby forcing the electrons in the wire to move, creating a flow of current. In most AC generators, the magnets move while the copper coils remain stationary. The north and south poles of the magnet cause the current to flow in opposite directions in the wire, thus the term "alternating current." 

In powerboats, the mechanical energy comes from small gas or diesel engines, and that's where most of the innovations have occurred. The same technological advancements that greatly improved performance and reduced emissions in the main propulsion engines finally started to filter down to generators. This is important because monitoring of generators is sometimes spotty at best.

Generators typically operate "out of sight, out of mind," meaning they don't traditionally enjoy the same level of monitoring and maintenance that the main power sources receive. And since generators often run many more hours per year than the mains, they usually need even more attention. Generators live a hard life. 

Recently, Onan incorporated electronic engine controls into the company's gensets, greatly improving monitoring capabilities. The new e-QD (electronic Quiet Diesel) Series Networked generators come with ratings from 4 to 99 kW, providing efficient power for virtually any boat. Onan also builds a line of e-QG (electronic-Quiet Gas) generators, as well. 

The network component enables you to monitor extensive engine and generator information, including AC voltage, AC frequency, coolant temperature, oil pressure, battery voltage and engine hours. 

Service technicians can access a wealth of diagnostic data, helping them evaluate operating conditions and perform service checks throughout the system. "Many gensets will trip a breaker when something has gone wrong; however, you're never really sure what happened," says Ann Gougebas, communications manager for Cummins Power Generation Onan. "With the diagnostic information that the Onan e-Series provides, knowing what happened may mean the difference between enjoying your weekend or waiting for a service call."

Operators access this information in one of three ways — through Onan's own networked e-Series digital display, through interfacing with the SmartCraft networking protocol or through the SAE J1939 CAN protocol. The SAE J1939 comes in handy on boats already using the same type of network for digital or computer display, but the choice of three separate systems provides maximum flexibility. With the e-Series Digital Display, for example, you can install up to three display heads per vessel. The display panel features a sealed enclosure that protects it from spray, and the optional display unit can be mounted on the genset or anywhere else.

The SmartCraft system consolidates data transmitted from several distinct sources through a common databus to a display unit, usually located at the helm. SmartCraft monitoring can combine functions of the main engines and the generator into a single display unit — a very helpful feature when space is limited. You get all the aforementioned engine and generator diagnostics, plus an alert to a prealarm condition. And if the genset shuts down for some reason, you receive a notification and a diagnostic text message.

In addition, the output frequency on the models from 4- to 27.5-kW can be switched manually between 50 and 60 Hz, so the same generator can be used in the United States, where 60 Hz is the norm, and overseas where many countries use 50 Hz.

At Westerbeke (www.westerbeke.com) a new line of Safe-CO gasoline generators drastically lowers carbon monoxide (CO) emissions, making them much safer to use. Carbon monoxide emissions kill quite a few people each year, including boaters. All internal combustion engines produce this deadly, odorless gas, but gas-engine emissions typically contain much higher CO levels than diesel exhaust. Poor installations that don't adequately prevent exhaust gases from entering the cabin can lead to tragedy. Westerbeke took a giant step forward in addressing the problem with the Safe-CO series. These units eliminate over 99 percent of carbon monoxide, more than typical carbureted and conventional EFI gas generators.  

Westerbeke utilized its own proprietary engineering breakthroughs, coupled with electronic fuel injection, to achieve these impressive reductions. The Safe-CO series comes in several sizes ranging from 5 to 25 kW. You can learn more about them at www.safecoproducts.com.

Northern Lights (www.northern-lights.com) also came up with a unique development in their new line of W-Series marine generators. The difference in this innovation andthe first two examples is that the change comes on the generator end rather than on the engine end of the genset.

The W-Series features a new auxiliary stator winding delivering dedicated power to a new DST-100-2FAK Automatic Voltage Regulator. Load changes or power corruption do not affect this auxiliary winding because it is separate from the main stator windings. That ensures that the AVR is always ready to instantly respond to large load increases such as when the air-conditioning compressor kicks on.

This auxiliary stator provides advantages like true 300-percent short-circuit capability, whereby the generator can produce a short-circuit current equal to three times its rated capacity. But even with these obvious advantages, the new W-Series is no larger than conventional Northern Lights gensets, making them perfect for retrofits. The W-Series comes in outputs between 8 and 33 kW.

All these technological advancements help ensure that one of the most vital pieces of equipment on your boat, your generator, provides years of smooth, quiet and uninterrupted electrical power — just like it was designed to do.