Day 7: power management on an ocean crossing

Yesterday I went to bed at 6:00 and Saskia took over. Just as she was coming up the wind picked up (finally) and there was no need to make any change in our sail set up! Great! That means I can go to sleep comfortably without hearing sails flapping, that really sounds like the boat is coming apart when you sit inside. After waking up I went about the usual: checked the batteries the consumption and charge, and adjust anything if necessary. We were producing plenty with the solar panels so I switched on the freezer, the inverter to charge the laptop and ran the water maker to fill the tanks. Power management has been a big thing in this trip. We have an OK sized but old power bank (500Ah, of which 250Ah are usable).But it’s never enough. If I run everything as per normal, I have to turn the engine ON in a day and a half. With the solar panels (2x100W on PWM controller plus a 340W on an MPPT controller) I can probably extend that by a day or so. But that’s still not enough. The solution is to only have the important things on. What are those for us: AIS, VHF, wind instruments, autopilot. These are ON 100% of the time. Then we have fridge, which we keep to the power setting 5 (out of 7), the USB sockets and the cabin lights. These are also always ON, but of course consumption varies on time of the day. The plotter and radar, are kept OFF but ready to be switched ON when needed. That’s because it draws so much power! And with an app on the phone to use as plotter, it’s really just the radar function that we might want at night. The freezer, like the plotter, takes t oo much power so it stays OFF for most of the time during passages. We used it as storage space, not as freezer. With this setup, we usually consume 50Ah between the time the solar panels can’t cope and the time they are able to produce enough to offset the demand. These days, with the good weather, strong daylight and low consumption, we have the batteries back to full before lunch. If things look positive, ie that the batteries will be filled during the day, we take the opportunity to run all other equipment we turned off. One of then is the watermaker. Alone it draws around 10Amp (for what it is, it’s not bad actually). Since we’re careful about our water consumption, within 30min the water tanks are full. Again, all looking good, we also charge the laptop via inverter, let the freezer cool off, and top-up the secondary power bank. These days we’ve been able to do this everyday, and are back to full power after lunch! We expect things to change when we start getting cloudy skies, but enjoy the time until then! Apart from that we had another pretty good day! We’ve been sunbathing and blasting 80’s and 90’s music on the cockpit. It feels great!! Feels like a summer’s lazy Sunday! If you want to check where we are, head to Sailing Saetta Saskia & Miguel