Hello all,

John Jeffery is selling new solar modules that are pretty much purposely made for the model solar car challenge. For further details see the Tasmanian website http://www.tassolarchallenge.org.

miseli

Just had a look.
They look great, very similar to the Scorpio panels in terms fill factor.

What sort of price are they selling for?

I can't be sure, but I think John said around the $12 - $13 mark. So around $5 or so less than the old dicksmith cells which is not too bad at all.

I will stick up a price with them once I get a definitive figure from John.

John reckoned he just about got 600 - 700mA Isc out of some that he tested outside in the full sun.

Because there is still a bit of room around the cells in the module, they could potentially still be made slightly smaller. I think John spoke about having some slightly longer 4 cell modules made to give 2V rather than the 1.5V. If he does get these in, I don't think that the price would increase a great deal and only 8 modules (or about $100) will then be required for a car panel.

miseli

Thanks for the link miseli! This really helps!

At last the new 4 cell modules are on their way! The first shipment is scheduled to leave China on the the 15th of May so I should have them a few days after that.
They are being made on the same backing as the 3 cell modules, that is, black fibreglass 62mm x 120mm x 3mm with large square solder pads on the back. They are made from the same first quality, laser etched and anti-reflective coated cells, about 16+% efficiency, FF 0.75+.
Despite being 4 cells they actually take up more of the available space. Unfortunately because there is a bit more active material plus the extra handling in mounting the extra cell they are going to cost me a dollar or two more.
The good news is that you will probably only need to use 8 modules rather than 10. This will make for a smaller, lighter panel and require less ballast for those capable of building small, efficient, light weight cars.
To approximate the module voltages multiply by 4/3 (so 8 modules will give a bit more voltage).
To approximate the module currents multiply by 4/5.
To approximate the module power multiply by 16/15.
Full test data will be available as soon as I can get proper tests done.
For the power freaks, you can use 10 modules and still stay under the 25Voc limit.

John, Put me down for ten of these as soon as they come in.
Ive always said the Scorpio panels output too much current, and are to fragile. And the DSE modules are garbage quality wise.
I think these will be perfect, and are priced good too.

I can supply these to a few schools here if you like.

The new 4 cell modules have just arrived, delivered on Sunday morning, would you believe.

A quick test of a pair of randomly selected modules aimed at the prevailing Tasmanian sun 5 minutes ago gave 425mA from the 4 cell module compared to 508mA from the 3 cell module.

The size is the same, 63mm x 120mm, but there is very little waste space on the modules.

Pricing to schools will be $14 + GST each, discounts for serious quantities, plus delivery. All I need is an official order and I will despatch same day with a tax invoice.

Ian Gardner will have full test data shortly.

Ian Gardner has provided the following test data for the new 4 cell modules. These figures suggest that the cells are very high quality.

50% Sun, 25C, AM1.5, 10 series modules.
Voc: 23.50 Vmp: 19.49 Imp: 0.241 Isc: 0.254 Pmax:4.70 FF:0.787

100% Sun, 25C, AM1.5, 10 series modules.
Voc: 24.37 Vmp: 19.75 Imp: 0.464 Isc: 0.491 Pmax: 9.16 FF: o.765

For less modules simply factor voltage and power.

In true Chinese fashion they have supplied modules with two different cell widths. These figures are for the 28mm wide cells but there are 25mm wide cells. Thankfully the different sizes are not mixed on modules. I have sorted the modules into the different sizes.

However, this gives teams a further option. By simply factoring the current and power by 25/28 further panel powers can be selected, depending on whether you are going for a light weight car or brute force.

Just also want to confirm Ians results.
These are very good quality cells, and fill factor and efficiencies are way up there.
Im getting FF > 0.77 at full sun.

Here are the I/V curves for the New Engelec 4 cell modules. Curves represent outputs for 10 modules configured in series.
For racing with these cells, i recommend 8 - 10 module designs.

These modules are currently, IMO, the best modules for solar car, boasting high efficiencies, high FF, great mechanical strength, lightweight design, and configurable to different powers/voltages depending on desired setup.

Test conditions are 50% and 100%. All output data is shown in attached excel files.

Test tools:
Calibrated Lightbox.
NanoMETER IV Sweeper
Fluke 289 DMM

Sounds like a good quality product.
I would love to support Ian, but the panels will be too heavy to use with a boat.
5 engelec panels will have a weight of 165 grams.
This compares to the scorpio panel weight of 40 grams.
The engelec panels weigh more than the total weight of our boat complete, using the scorpio panel.
Lighter panels please.
Cheers

Hello,

Welcome to the forum.

You are quite correct in saying that John's new Engelec cells are too heavy for the boats. These were specifically designed for use in the car event and are much more robust. The cars must abide by a power to weight panel ballasting formula and so the extra panel weight just means a little less dead weight needs to be carried.

For the boat event, it's pretty hard to beat the panels Scorpio make and you will not find a better panel out there sold commercially. The only way these can really be bettered is if you go and make your own from higher efficiency bare cells.

miseli