Watts, Amps, and a big fat headache

One of the things on The List (you know the one that Tim threw away and I rescued from the trash...) was to do our electrical consumption spreadsheet so we could plan what we were going to need in the way of solar panels and wind generator. I had originally been scheduled to do 2 canvas jobs this weekend but they both bailed for various reasons so I was left with a rainy weekend and nothing to do. There was no more opportunity for excuses so I dug out my spreadsheet, reading glasses, scrap paper and pen and set to work.

I started at the bow in the V-berth and worked my way to the stern, checking each DC item in the boat and marking it in the spreadsheet - watts, amps, average daily use, part numbers and where we bought them, and running total. I had previously done some research on boats about the size of ours whose owners had blogged about their total usage and they seem to run between 190 amps per day and 250 amps. (Comments please if yours is very different and why.) As I worked, I estimated high on everything since I have only our current use as weekend liveaboards and absolutely NO idea what our actual use is going to be while cruising. I came in at 205 amps but there are several things we are going to change to curb that, including 2 cabin fans that are hogs at 10 watts each and run for a good part of each day. One thing I noticed while doing some research on things that were already installed in the boat and that we had not bought since, was that even two years makes a HUGE difference in the efficiency of models of things. Take for instance our bilge pump. While I don' t have my spreadsheet right in front of me  to give you exact figures (working on the marina computer), our pump uses more than twice the amperage that the current model of it uses. While I realize we can't replace everything electrical in the boat, there are certain things that stick out on my spreadsheet that can be replaced relatively inexpensively. Since electricity is a currency on the boat, sometimes it pays to spend a little more for the product in order to save on your usage.  We have already replaced all our lightbulbs with LEDs, and the spreadsheet includes our new refrigerator which we have yet to install, so we're already moving in the direction of self-sufficiency.

I did learn a ton this weekend about electricity, a subject that has not been a good one for me prior to this, and I feel pretty confident that we can meet our power needs with a little creative thinking. After Tim reviews my spreadsheet I'll post it for you all to peruse. By the way, he is going to rest a little now because I've been driving him crazy with all the questions :)