If you only use your boat occasionally — or rarely drink coffee — instant coffee can be a good solution for the times when you do want it. As long as you can heat water and have something to drink it from, you can have a cup of coffee pretty quickly.
Most boats actually carry some instant coffee onboard as a backup method for times when it’s just too rough (or there’s no electricity) for making coffee any other way. For use underway, boil water in a tea kettle to reduce the chances of hot water sloshing out of the pan, put (or wedge) mugs in the sink, then pour the water into them.
Pros: Can make any number of cups, fast, very low space required, no electricity needed, no glass involved, easy to make underway
Cons: Most people just don’t like it as well as brewed coffee
Keeping it hot: Put hot water in a good Thermos or airpot and make more as needed
Cost: very low – can use any pan you already have, although a tea kettle is safer for handling boiling water.
By far the best instant I’ve tried is Starbucks VIA, which other reviewers also say is way above other instant coffees, but can’t compete with fresh-ground premium coffee.
It comes in single-serving packets, ready to mix with 8 ounces of boiling water, in a variety of roasts and flavors. Most supermarkets have one or two varieties, Starbucks shops usually have a good selection, or you can buy online:
Note that most mugs hold 12 to 16 ounces of coffee, so either adjust the amount of coffee you’re using or don’t fill your mug full of water.