Apr 072011

If you’ve been following this blog you know that I am close to over zealous when it comes to power consumption. I just ran a test. 18 interior lamps lit at dimmed comfort levels. Running lights on. Main computer and all navigation instruments running. Stereo on and playing music. VHF and AIS radio on standby. Total power consumption was 6.4 A at 12V equal to about 77 watts. Not bad!

Jun 302010

In governments and in sailing yachts….

Since the Journeyman aims to be an environmentally friendly yacht in all respects, I have decided not to fit any generator. At all. Not even a shore power charger! Well… that’s maybe also because shore power is a dangerous thing to have in an aluminum yacht to start with.

Anyway, we will rely 100% on solar power. To be able to fit as much solar power on the deck-house roof as possible I am using so called back-contact solar cells, which have a higher efficiency than traditional marine solar panels. These panels do have the issue that you can’t connect them all to the same charge regulator, due to electrostatic charge buildups that destroy performance.

So instead I am fitting each solar panel, 8 in total, with its own maximum power point tracking regulator. This means that each individual panel will be used to the maximum extent possible at all times, which is a good thing when some panels are partly shaded or at bad angles to the sun. As you can guess this happens pretty much all the time.

May 252010

One of the top electric energy consumers on a yacht is the fridge and freezer. The efficiency of the machines that take the heat out of the cooled space is heavily dependent on how efficiently the heat energy can be removed from the cooling liquid.

Most standard yachts use a cooling element with a fan, sitting inside the boat. This does not work well at all when you are in warm climates, and it is noisy. As an alternative you can cool the liquid using seawater, but the heat exchangers commercially available for this are always made of bronze, which is a big no-no on aluminum hulls.

But aluminum itself is a great heat conductor, so I decided to put the heat exchanger directly inside the hull itself instead. The hull plate is very efficiently cooled by the surrounding water. This way I get better cooling, lower power consumption and no noise. The two heat exchangers are also the last thing getting mounted before we start to paint the hull inside.

Feb 082010

Today work started on the engine mounting bracket. We unpacked and assembled the engine to make sure its dimensions matched the drawings I was given 18 months ago. It didn’t, of course.

The engine is just one of many many pieces of equipment that will be installed, but it still feels like a bit of a milestone!

Yanmar was selected as the supplier because it is the brand that has the best availability of service and spare parts across the world. By a large margin.

We will also make two changes to the engine:

The electric system will be modified to not use the engine chassis as ground. If the chassis is grounded it will allow corrosion currents to run between all electric equipment and the hull. This is not a good idea on an aluminum boat.

We will also fit NMEA2000 controlled throttle and gearbox actuators, to allow the engine to be controlled from both the two steering positions in the cockpit and from inside the deckhouse.