A Competitors spiel on their BOOST model

[Westbranch]

After reading this  article http://www.bostonmagazine.com/news/blog/2014/11/14/vecna-cto-solar-powered-vw-bus/
and getting some specs from the creator of the solar bus...  where they use a GVBoost from Genasun to increase from 12V to 48V

I read about the GV-Boost 12-48 model  CC's.
http://genasun.com/all-products/solar-charge-controllers/for-lead/gvb-8a-pb-solar-boost-controller/

NOTE The last line...

Genasun GV-Boost 105-350W Solar Boost Charge Controller with MPPT

Want to see a 27V grid-tie panel charge a 48V battery pack? Get a GVB.
Most solar charge controllers move power from a higher voltage panel to a lower voltage battery bank.  The GVB-series controllers, in contrast, pump electricity up hill. These controllers will take a standard 12V panel and boost the voltage to charge a 24V, 36V or 48V battery pack.  In fact, the GVB's will work with almost any panel that's below your battery voltage. This makes finding a good panel easy:  just make sure to stay below 8A panel current and 63 Volts (open circuit). Larger panels are cheaper per Watt than smaller panels, so using one large panel and a boost controller results in a significantly lower system cost than smaller panels in series with a conventional charge controller.

Mission-Critical Reliability
Genasun controllers are deployed to the most remote locations on earth. They endure years at sea, harsh Antarctic winters, freezing conditions in the upper atmosphere on solar powered airplanes, and in a few off-the-map locations. Made in the USA, each controller is put through complete electrical testing to ensure reliability. If you need mission-critical power, this is your controller.

High-Speed MPPT: Always on Target
Not all Maximum Power Point Tracking controllers were created equally. Most use a sweep and sleep method that scans the entire voltage range every 30-60 seconds. That's okay for a clear day, with a stationary panel. But moving vehicles and changing cloud cover require a faster, more advanced controller. Genasun controllers adapt to changing light conditions 15 times every second. They are always on target, capturing every bit of available sunshine. Simply put, other controllers can't keep up.

could not find much tech  data to support this claim... just this

http://genasun.com/all-products/solar-charge-controllers/for-lead/gvb-8a-pb-solar-boost-controller/


boB, comments?

[Halfcrazy]

Wow I just looked at it. $255 bucks for the one that boosts.... And it is limited to 8A in MAX that makes me a little nervous as most panels are over 8 amps ISC

That said I suppose if you had a 48v battery and had to charge with a single panel it would be the affordable way to go but dang thats almost the cost of a 30 amp MPPT controller and it looks like it is fairly limited in function.

[Westbranch]

Yes that (8A) limit is probably why they chose 12V  panels, the owner said that they wanted a CC on each panel so as to be as efficient and dynamic as possible, mainly from shade issues while driving.  Not quite Off Grid PV issues...

[vtmaps]

Someone from Genasun posted over at NAWS:
http://forum.solar-electric.com/showthread.php?20091-MPPT-with-voltage-boost&p=159439#post159439

Boost controllers make the most sense in applications where you only want to use one panel to charge a higher voltage battery. The prime example of this is a golf cart, which typically has a 36V or 48V battery, and has room for only one panel on the roof. There aren't many panels out there with a high enough voltage to charge a 36V or 48V battery. The boost controller gives solar golf cart kit manufacturers flexibility to choose more commonly available, cost effective panels.

Also here: http://forum.solar-electric.com/showthread.php?16470-2-60W-panels-in-series-or-parallel&p=158559#post158559

--vtMaps

[Westbranch]

To it looks like  the VW van/bus is a rather unique application that makes good use if the dynamic MPPT of 15 - 20 times per second as the van drives here and there in traffic, using 12V  panels and a 48V bank.

[boB]

Yes, I've seen this before online but have never played with one.  I would if I had one to look at.

It may well be fine for small-ish systems like on a small bus like vehicle with one module or in
side of the road signs or parking meters (also mentioned I think).

8 amps is barely one module's Isc and sometimes Imp which was pointed out.

Can't connect it up per NEC code (if needed).

Not sure how it can sweep 15 to 20 times per second and stay on the max power point voltage ?
That alone would be interesting to see what they are doing.

But I probably shouldn't even do that as I am short on time (but aren't we all ?)...

boB