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A Bright Idea

April 16, 2018

Swapping out halogen bulbs for LEDs

Boats and LED lights had a chequered relationship for many years. The options were limited meaning expensive new light fittings often needed to be purchased. ’24 volt’ bulbs were often produced without considering that when the chargers or alternators are running the system voltage is closer to 28 volts, leading to blown bulbs. Well, as Dylan said… the times they are a changin’

Here at Berthon we are swapping out halogen bulbs for LEDs almost every week. There is an array of good quality bulbs to choose from, rated 10-30V and available with different connectors such as G4 or mini bayonet meaning existing light fittings can often be retained, keeping the cost down.

There are two big advantages to fitting LED lights. The first is safety; halogen lights can get very hot and are therefore a fire risk; LEDs don’t heat up anywhere near as much. The second, which requires further explanation, is that LEDs are considerably more efficient and for increasingly power hungry cruisers, this makes them a must have. The example below shows that running incandescent bulbs for four hours could take up 33% of usable battery capacity, whereas LEDs would only take 4%:

Typical 35-45ft sailing yacht with 12V system

Battery bank capacity:400Ah

Usable battery capacity: 200Ah (batteries cannot be run right down to empty)

Typical incandescent bulb 10W Typical LED 1.2W
20 bulbs 200W 20 bulbs 24W
Current consumed in 4 hours 67 ah Current consumed in 4 hours 8ah
Percentage of usable battery capacity 33% Percentage of usable battery capacity 4%

For more information about upgrading your yacht’s electronics please visit our marine electronics page or contact our electronics manager Henry Castledine.

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