is an MPPT worthwhile?

I just started a different thread about battery capacity for a modest 2x100W panel solar system connected in parallel.
I would like to know if a MPPT would provide any additional power if the panels connected in parallel are already at a workable charging voltage for a 12V system (17-18V). There is a bunch of hype about how well MPPT track a panel's optimal voltage it has me wondering if I could squeeze a few more mAh out of the array.
I would like to know if a MPPT would provide any additional power if the panels connected in parallel are already at a workable charging voltage for a 12V system (17-18V). There is a bunch of hype about how well MPPT track a panel's optimal voltage it has me wondering if I could squeeze a few more mAh out of the array.
Comments
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
For systems over 800 Watts, you can use >200 Watt panels that can be down towards $0.50 per Watt. And much more expensive MPPT solar charge controller. Also, with larger arrays and arrays that are longer distances from the charge controller/battery shed, you can use a higher Vmp-array and smaller copper wiring (save money on panels and copper).
I highly suggest that you do a few paper designs and see how the decisions/choices are made.
First, define your loads (energy needs)--And remember that conservation is almost always cheaper than generating the power. When the system will be installed (nearest major city--Figure out hours of sun), is this a seasonal system or full time off grid. Use a genset for backup power or pure solar, etc.
Once you have that information, then do a "cook book" paper system design. And lastly pick the hardware that supports your needs.
There are always multiple answers possible--So designing several systems (cost vs options/needs). Then pick a design and buy the hardware.
-Bill
As Bill said, lots of paper designs, I'd also write what you intend to do with your system and look to the future.
Will you end up at a higher voltage system?
Will you never increase the size?
Are you moving and want to maintain as simple a system as possible... etc
Ran my tiny house on a 60amp PWM charge controller feeding a 24 volt battery. It worked fine, fridge a little air conditioning in the summer. I have a couple MPPT type charge controllers now and a bigger system and home...
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
A epever mppt controller $100 for a 10% increase.
I ran 2 separate 12 volt 400 watt systems. 1 with pwm all in parallel.
and 1 mppt all panels in series.
If your panels are close I would stay with pwm.
If you find you need more power just add panels.
Not saying it's the right way but I did not use a combiner box.
6 230ah GC @36 volts
18 amp accusense charger. 3650 champion