As navigation and engine technology improve, a growing number of electronic solutions are available to help recreational captains estimate and track fuel consumption.

Indeed, fuel data is becoming standard fare on power boats large and small as new engines offer advanced monitoring capabilities and aftermarket solutions grow more affordable. It is now possible to buy and install a fuel monitor that derives information directly from your fuel lines for less than $1,000 – a lot less, in some cases.

While no captain should rely on electronics for vital data, especially when making long coastal runs or offshore passages, fuel monitors can be a great help for those making shorter trips or who simply want to pursue better fuel economy.

MONITORING

Active fuel monitors derive data directly from the fuel lines, metering the fuel that passes – gas or diesel – and using a computer to calculate information such as miles per gallon and gallons per hour.

On a new boat, the chances are good that this functionality is built right into the engine. Many new engines offer advanced monitoring, sending data on everything from fuel consumption to exhaust temperature to the cockpit electronically, where it reads out on a dedicated monitor or a navigation display.

There are many options for older boats too. Aftermarket products have become cheaper and more robust, and many are designed to be installed by do-it-yourselfers. For diesels, Flo-Scan is one popular brand. For gas engines, Lowrance, Navman and Flo-Scan all make well-regarded products.

When choosing a flow meter, compare carefully. Pay attention to the installation that is required, which can require more than a little plumbing and wiring – especially if you have two helm stations. Read the documentation that comes with the unit, such as manual, instructions and tutorials, before you buy. Also be aware of the quality of tech support that is offered. Cutting into your fuel system is not a project for the faint of heart and you want to make sure the job gets done properly. If you have any doubts about your own ability, call in a pro.

One good source of information, both for shopping and installation, is an online forum like TheHullTruth.com. There are voluminous threads containing debate on which unit is best, tips on how to install them and advice on troubleshooting. You may have to endure some exaggerated opinions, but the information from boaters who have already been down this road is worth it. If you don't find exactly what you are looking for, post a question of your own. On this subject, you will get many answers.

CALCULATORS

Another, less-invasive option is a computer-based fuel calculator, which is a program that allows you to input basic information and derive more advanced data without having to do the math yourself – or cut into your fuel system.

Unlike flow meters, calculators deal with theory – they are not monitoring your fuel directly. And they are only as good as the numbers you put in. But they do have their place as a convenient auxiliary tool.

Fuel calculators are often found in high-end navigation software programs, such as NavSim's BoatCruiser, Nobeltec's VNS and Admiral, and MaxSea. Some log applications may offer similar functions.

While a fuel calculator is probably not a reason to buy one of these programs – they can cost hundreds of dollars – it is worth checking on if you are in the market for a navigation or log package.