How is our Solar System working, one month on?
The system was made up simply with some guidance from my mate, Lachlan, at Solar Century and me just seeing what fitted where! No real measurements where taken, no complicated computer aided design – just trial and error. It is loosely based upon the “Solar Rollers” which we helped to design for SolarAid to charge mobile phones at festivals.
Due to leaving things right to the last minute the solar system was one of the last bits of the landcruiser to finish before we left, this meant that the “trail” would actually be the trip!
I’ll start with the top and the most important Solar PV modules. It was a stroke of luck the Beco Solar had some used 12 volt BP 380 panels (modules) that they where willing to give to us – but perhaps even more lucky that they actually fitted around the roof top tents almost perfectly. It takes two people around 15 minutes to unplug, take down the panels and put up the roof top tents. It is a bit of a palaver to do twice a day – but not that bad. There is however some very natural about finding East every night so the modules are working as soon as the sun rises – it really helps us feel at one with the site.
Now we are in Egypt and it has been bright and sunny every day we have had plenty of power, so much power we don’t know what to do with it! Anyone want there mobile / laptop charged? Energy efficiency in the UK has taught me to always unplug everything – a single mobile phone charger left in the socket at home over the year can cost you £50 in electricity but having lots of power may mean that “bad” habits may creep in! We don’t really have to worry. (Apart from overheating the sockets). We have the luxury of boiling the water for washing up in the “Zero Carbon Kettle” as well as endless cups of tea… As the system is completely independent from the engine batteries it is very useful to be able to leave things on charge while we are not in the vehicle and then not have to worry about the car not starting. It also means that we can have the lights on and the stereo playing as late as we like when camping in the middle of the desert.
In Libya and Europe we were a bit more careful, only charging laptops when it was sunny and keeping the screen of the stereo off. Some of the days were very cloudy and some evenings we did have a “red, low battery” light – but it was never low enough to cut out.
The engine ancillary solar system (cooling fan / power steering) also seems to be working well. We have been quite conservative with the power steering (it is only needed under 20mph), only switching it on when having to turn around, but with more sun we will probably use it a bit more (less good for my upper body exercises!). Being conservative with the power steering means there has always been plenty of power for the engine cooling fan – which is vital in heavy traffic or when the vehicle is moving slowly. A solar cooling fan makes a lot of sense, when there is lots of power going into the modules – this is when cooling fans are likely to be needed (in hotter sunnier weather!). It did however still work perfectly when we got stuck in the sand dunes near Siwa, in the middle of the night. I have now adjusted the fan so it comes on sooner, this should help the engine stay at optimum temperature.
The major problem with engine driven cooling systems (like the landcruiser was) is that the cooling system stops working as soon as you switch the engine off. The coolant that is in the engine at that time doesn’t move and just heats up. It can heat up so much that it expands and eventually cracks the engine –and / or blows the head gasket (this is called heat soak). The electric fan switches on or off from a temperature switch, it will switch on even if the engine is off. The fan often kicks in a couple of seconds after the engine has been switch off – helping to prevent heat soak. It would be even better if I had had the time and funds to fit an electric water pump – helping to cool the engine down after a long drive more evenly. Would anybody like to send me one?!
While the Solar System has given the car lots of practical benefits, the main aim was to help cut our emissions. This is very difficult to measure as there are so many variables to the landcruiser fuel consumption (road conditions, weather, fuel quality, how much weight we are carrying and how the vehicle is being driven) but the conversion simply must be saving carbon. The energy would have had to come from the diesel engine. I will post up our fuel consumption shortly – we are just trying to accurately measure our distances (the cars speedo seems to be reading around 5% under what we are actually doing, according to 2x GPS, maps, Google and road signs).
Having the Solar system also helps us to explain to people about the aims of the charity SolarAid. Plugging a light straight into the modules is a great explanation to anyone to how well the technology works.
It is clear that new environmental technologies will actually improve our way of life and the idea that we have to go back to a time of shortage (i.e. the 1940’s) to save the planet is not necessarily needed. We must never forget how technology has helped to changed society, particularly labour saving devices and the role of women.
So far all is very good on the Solar front – just perhaps we could have done with a few more car parts powered by it…