Boat Electrical Systems



As we slowly moved aboard sailing boats we realized how much modern suburban life depends on electricity on demand. What room in a house or workplace other than wet areas such as bathrooms doesn’t have a power outlet on each wall?


In the late 90s when we bought the first Maringret the only option for lighting was incandescent lighting. As we started to determine our needs we searched for solutions, both mainstream and alternative – this collection of pages details that journey. Lighting technology (e.g. LEDs) has moved a long way during the same period, batteries and battery management are moving although at a slower pace.


To encompass our electrical work we have organised a collection of pages as follows:

Soft vs Hard Energy – hard (engine or shore power) energy vs soft (wind, sun, water) energy
Batteries Overview & Selection – wet acid vs gel cell vs AGM battery types
Battery Capacity Calculation – determining how much electricity is required and what battery capacity
• Energy Collection
– wind generator types and sizes
– solar panel types and sizes
Battery Charging – getting the power collected into the batteries as efficiently as possible
Power Management – managing and controlling the power in the batteries


  • Any area of technology can quickly be altered by new discoveries, low voltage electrical and batteries have certainly seen this. What might be the optimum solution in one year may be partially or totally obsoleted by developments one year later.
  • Generally the persons selling the technology have not been overly knowledgeable. We have relied heavily on websites, printed books, talking to early adopters and large scale users.
  • Distribution of new technology is not managed in any way and often during the introduction large discrepancies exist in pricing between one area and another. in this case it can be worthwhile to pay the shipping from another area. An example is solar panels in Europe where some governments grant them tax free status while other apply full VAT (a difference in the price of up to 25% or more).
  • Realise that in a moving field any solution will slowly age as new technologies become available.


The solutions we adopted have generally stayed in place. It is now 10 and 20 years since we made our surveys – the equipment we bought is now starting to fail (presumably due to old age). The improvement continues but now seems to be more incremental than revolutionary.

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