Thames Solar Cruise Cancelled -Why?

It is with regret that I will have to defer my cruise until next year.

The remarkable results I achieved with my early trials with a small solar panel and an 8 year old battery have not been matched when I upgraded for this cruise. As a result it will be impossible for me to meet the timetable I have arranged and it would take in the region of 2 weeks to complete the cruise.

I am grateful to Mike Manisty for sharing his experiences of a 3 week cruise upstream from Westminster to Lechlade in 2009 and for lending me some panels and test equipment. If the 2 multimeters I ordered on the internet had worked on arrival I would have discovered the shortfall sooner.

I was trying to run for 8 to 10 hours per day but this does not give sufficient time for the battery to recharge so solar input must average the same as electric output. This is not possible as the days get shorter.

When panels are available based on the latest research they could have 6 times the power and be a completely different proposition.
http://www.naturalnews.com/028691_solar_cells_efficiency.html

Sorry for any inconvenience caused. If you have arranged a meeting locally I will be pleased to come without boat to talk further about solar cruising and home renovation for 2050.

It would be good to prepare for June next year with another boat for company.

For any thinking of a similar trip let me share my mistakes. The good results of two trials led me to neglect the maths and concentrate on the publicity through July. I did want to calculate the watts I could pick up in various weathers so ordered a multimeter for the purpose. When it arrived and did not work I just ordered another more expensive one and this too did not work.

Mike Manisty lent me panels and, as I tested them in the garden using his more sophisticated controller, I realised I had over estimated the travelling I can do in a day.

Typically an 80 watt panel facing the sun generates 4.8 amps at 13.5 volts to charge a battery. This drops to 3 amps if the panel it flat on a table or on top of a boat. Any obstruction like an arm casting a shadow over 10% of the panel drops the charge to 1 amp. A cloud will drop the charge to 1 amp if the sky is still quite bright but as evening draws on the charge will drop to 0.3 amps.

These are good practical measurements taken on August 8th at 5pm which may help me and others to get the best out of solar energy on the water. I will add some more measurements later.