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Emergency electrical power

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What is the issue?
If you flatten your battery, unless it is a particularly small engine that can be cranked over manually, you will be without engine power and be crippled for power aboard.

Why address this?
Discharged batteries will make the vessel completely dependant upon its sails and place instrumentation and navigation lights in jeopardy. In certain situations this makes for hardship and could develop into a situation where the vessel could be lost.

How to address this?
Invest in a small portable petrol generator so discharged batteries can be replenished in a reasonable amount of time - see figure 1.

This is not something that would occur to you departing on a circumnavigation but I came very close in the Indian Ocean to loosing the engine due to battery discharge. I would add a generator to my cruising list from that point on.

We were having a rough ride and were forced to hove too many times to deal with challenging squalls bending the wind around 180 degrees. Because we had not got a swan neck (that’s another tip) at the time we unwittingly were taking water down the exhaust pipe and down into the engine when we hove too. Suffice to say after coming out of a prolonged session we spun the engine over and over and it would not start. We believed it was lost and we had run out of battery power to turn it over again. It was literally on the last kick of battery juice our reliable engine coughed and then miraculously sprung to life.

We drew deep breaths and thanked our lucky stars for that moment as it was on the very last turn of the key. I started to consider what would have happened had that engine not started at the last moment. Very shortly at Galle Harbour in Sri Lanka I was about to discover two possible outcomes. Two other boats departed at similar times to us to Sri Lanka and they had battery discharge problems.

The first was a solo sailor who could not start the engine two weeks out in the highly unpredictable conditions we experienced. As the area south of Sri Lanka is a major shipping area she had limited power for navigation lights, VHF and instrumentation. This forced her to stay practically awake for two weeks trying to dodge and sail her way through the weight of shipping that turns the corner. Completely fatigued she made it to 400 metres off the entrance of Galle harbour and was within the walls practically. Just then the wind died and within twenty minutes the surf pushed the vessel up onto the reefs. She clambered out to the shore line under the Galle fort but the vessel was a total loss.

The latter boat had a solid crew with more good fortune. They lost all power because the batteries were low on water and over cooked in the marina by a charger prior to departure. The vessel had zero engine power and zero instrumentation they realised after departing. This brought the vessel back to 19th Century sailing techniques and hardships for the passage but they got the vessel in.

In both these cases the situation could be made dramatically better by having a generator and some petrol. It is like have energy on reserve. You may of course have a diesel generator but this is a much more expensive proposition.

Since then I would place a generator on my list of cruising essentials. One other key point about a generator is this is a useful item to have on a boat. It is not just one of those precautionary acquisitions that you may be able say once in a long cruising career that investment paid off and you rejoice. A generator can turn in good service and earn its keep.

If you include just these three tools with the generator you can dramatically simplify on board development and repair whilst cruising.

(i) A 100-125mm grinder, with metal cutting blades, sanding disk, grind stone and wire brush - see figure 2.

(ii) A jig saw - see figure 2.

(iii) A rechargeable screwdriver.
If you are familiar with cooler latitudes, you will find the tropical environment surprisingly debilitating when it comes to manual labour. It is utterly amazing just how slow progress can be and how little can be done. Power tools will make a dramatic difference to what you will take on and what may be accomplished.

With thanks to:
Michael Harpur, Yacht Obsession.

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