In line with our “GREEN” credentials, Sue & I have nearly become energy self sufficient. (PS. Don’t tell anybody I have two Monaro V8’s). This is achieved by tidial, solar , wind and weight energy forms. The tidial energy can add or substract up to 2 knots to our boat speed. Murphy’s law is that the tide will always be against you.
We have a 400 Watt Duo-Gen water / wind generator which takes about half a knot of the yacht speed. It can also be converted to a wind unit by disconnecting the propellor, inverting the unit in the air and attaching the 6 wind blades to a central hub.
Our solar power plant is 6 off, 80 Watt Crystalline Silcon Photovoltaic Cell modules mounted on the roof of the hard dodger. These cells are connected to the HOUSE battery via a intelligent switch regulator which cuts in @ 13.4 VDC and cuts out @ 14.0 VDC. There is also a boost mode which cuts in @ 12.5 VDC. Our solar cells installation is shown below.
We have just added a 250W wind turbine by Air Breeze which has a cut-in wind speed of 3 knots and produces 250W @ 25 knots. It has a built-in microprocessor to control the battery charging and wind turbine speed. The unit freely spins until the reguator cut-out point of about 14.5 volts is arrived at and the unit then spins much slower until the battery voltage falls below the cut-in point. If the wind speed > 32 knots, the unit enters a STALL mode and the unit is braked to a very low speed to protect the blades from destruction.
The weight form of energy is movable ballast in the form of the crew. When hard into the wind, we move the heaviest people to the windward side to counteract the keeling moment of the wind. This flattens out the lean of the yacht a bit and we gain a half knot or so up wind. We normally feed up the crew members and lengthen their pit stops to be better movable ballast.
Gypses Rover Daily Average Power Usage (Based on a nominal 12 VDC system)
|Item||Current(Amps)||Current / day (Amp-Hours)||Comment about usage|
|Fridge / Freezer||10||80||Use top loading fridge & set thermostat to minimum. Turn off on cold nights|
|Navigation Lights||1||10||Replace bulbs with LED’s|
|Navigation Equipment||4||30||Includes instruments, chartplotter & auto-pilot.If the yacht is well balanced, the Auto-pilot hardly does any work|
|VHF Radio||0.4||10||Receive mode only|
|Interior Lighting||5||15||Have replaced some bulbs with LED’s|
|TV||5||5||Uses a lot of power. Luxury item for shore power only|
|Computer||3||6||Power hunger Laptop. Better to go with smaller screen , slower CPU and longer battery life with solid state memory|
|Toilet Macerator||10||2||Use for very small time only|
|Other Stuff||1||2||Gas Detector Solenoid valve, etc|
From the above table, we need about 160 AmpHrs per day which is supplied by 100 AmpHrs of Solar Power and 60 AmpHrs of Wind / Water Power to break even. The Wind / Water Power can quiet easily exceed this both during the day and night operation. We have two independant battery systems. The Motor batteries is only for starting the diesel engine, bowthruster & anchor winch operation. The House system consists of 4 off, 250 Amp Hr, AGM type batteries connected in parallel. There is an 8 KVA diesel generator on board to charge the batteries, as well as a 80 amp Yanmar alternator and a 150 amp Balmor Alternator off the engine.