Friday, November 15, 2013

Power to the People

Managing resources is the key to live (well) cruising on a sailboat (i.e. away from the
dock and land). There are many different kinds of resources on our boat; diesel, gas,
food, water, drinking water, clean clothes, space and even the holding tank. In future
posts I'd like to discuss ways of efficiently managing each of these resources but today
I'd like to focus specifically on electrical power. As we take a day off traveling today
("gale day") and just swing on the hook managing our very limited electricity resources
is paramount.
Managing resources can be split into three topics: (1)storage, (2)output, (3)input

Storage
Storage (i.e. for immediate use) of electricity is obviously in the form of batteries. We
have two boat batteries:
Motomaster Nautilus 900amp Reserve Capacity/Amp Hour, 205min/115Ah
Motomaster Nautilus 730amp Reserve Capacity/Amp Hour, 160min/100Ah
One battery we use as the house battery when we are at anchor (i.e. for cabin lights,
water pressure, radio, VHF radio, masthead light, charging other devices, etc.)
One battery we strictly reserve for starting the diesel engine.
In addition to the boat batteries there a many other device batteries, rechargeable and
single use. Laptops, phones, radios, flashlights, cameras, tools. One of our frustrations
is the wide variety of chargers that we have to keep on hand to recharge each of these
devices. We have mess of wires plugs, taking up space (another limited resource).

Output
The use of our various devices drains their particular batteries. I would say that devicewise our biggest energy expenditure are probably laptop, US cell phone (mostlytethering for Internet), our iPhones and VHF radios.
The biggest drain on our battery bank is by far our refrigerator, so much so that if the
batteries are not actually being recharged we can't run the refrigerator just off the battery. This makes keeping food a challenge, a topic for another post.
The second biggest consumer is lighting, specifically our incandescent light bulbs. While these bulbs produce a nice warm light they are wildly inefficient and most energy is lost to heat. Comparatively new LED bulbs consume a only fraction of the power. LED's produce a slightly less appealing light colour (although they now come in “warm white”) but the power savings are significant. We have a few installed as test. We have a bunch more on order and soon the entire cabin will be LED. One incandescent bulb that is harder to change is the masthead light that is left on all night when we're at anchor. Experience has shown that this bulb alone being left on all night can drain the entire battery by morning. This bulb is a different size than those in the cabin and replacing it with an LED requires going up the mast with tools, etc. so unfortunately we'll have to wait.

Other boat battery power drains include:
Water Pressure Pump
Devices (laptops, phones, handheld VHF radios, etc.)
Radio & Speakers
VHF Radio


Input
Currently on Topanga we only have two electrical generation sources.
Our primary diesel engine that runs a 35amp alternator. When we're underway using the engine we produce plenty of energy. Not only do the boat batteries get fully charged but we have a prioritized list of devices to recharge through a 12V DC cigarette lighter outlet. Because some of our devices can only be charged with AC we also have an inverter that accepts regular two-pronged house plugs. Recently we've just upgraded to another inverter that, in addition to the regular two-prong wall plug, also has a USB port. So now we can charge two things at the same time. This is big news for us!

Running diesel engine for short periods at low loads is actually unhealthy for it. Diesel engines like to be run long & hard. When we're at anchor and the batteries are depleted we run our portable gas generator. Some bigger / newer boats have generators integrated. We do not. Started like a pull lawnmower, the generator can produce a whopping 2000Watts. It sits up on deck and we run an extension cord to the boat's shore power plug (just as if we were plugging into dock power). When the generator is running everything gets charged; the batteries and all devices which are plugged into the many AC house outlets in every room. We make sure everything is plugged in (we have a checklist so we don't forget anything). Cassandra even takes advantage to straighten her hair. Many people who are at anchor for extended periods run their generator for one hour in the morning and one in the evening. It is the fastest way to recharge everything. That being said, frankly, I'm not such a huge fan of portable gas generators. Due to its size and contents (gas) we have to keep it up on deck. This takes up valuable deck space, risks falling over in rough seas (although we have it securely strapped to the mast it did fall over once, in that same rogue wave that took our dinghy). Bright red and up on deck it is also a highly visible target for thieves so we have to lock it to the mast as well. It's noisy. It makes exhaust. Like any internal combustion engine it requires maintenance (oil changes, filters, etc.). Its vibrations can be felt throughout the boat which I fear will cause cracks in the gelcoat (I've taken to sliding a cockpit cushion under it to dampen the vibrations).

If I had my dithers we'd have additional sources of electricity like solar panels and a wind generator. These are free and limitless, well as long as there's sun and wind, which there often is. These two energy sources further build on the sailing philosophy of directly harnessing natures power. Unfortunately these both have significant purchase costs and take complex installation & wiring Choices had to be made for departure and the gas generator was the obvious one.

One little device onboard that is energy independent is our Eton Crank / Solar Radio (AM/FM/Weather, Flashlight and USB Charger. My sister got it for us after her experience without power during Super Storm Sandy last year. Under license from the Red Cross and meant for disaster situations this little device can be charged by a little solar panel on the top or can be hand cranked to produce energy. Two minutes of cranking gets about twenty minutes of radio play, thirty minutes of LED flashlight. USB charging however takes significantly more cranking. Just for fun I tested it out and it took about five minutes of cranking to increase my iPhone's battery charge by only 1%. Not stellar but, useful if you're in a pinch. If we're at anchor for extended periods we use the crank radio instead of the boat radio for music and news. It's kind of a fun thing to crank it yourself when it dies (and also a bit of exercise...)

As you can see electrical power is of prime concern to us on a constant basis and we are very conscious of our energy usage. Remarkable to be living "off the grid". Stark contrast to how we used to live on land with hardly a care for electrical energy, especially in Quebec where electrical energy is plentiful and cheap. Next time you flip a light switch or turn on the TV think of us.

Mission Control Panel. We look at this a lot!

LED vs. Incandescent... uncomfortable bedfellows


Plus one iPhone that took this photo

Lil' Red

Perpetual motion machine?? Almost!


1 comment:

  1. Hey John, just have Cassie use that sewing machine to make you guys a cover for the bright red generator. It will at least be less of a beacon to thieves.
    Off to turn off the extra lights throughout the condo.
    Still stalking you both,
    Jennifer and Mark

    ReplyDelete