Panel Optimization Part 3

Last week, while in the San Francisco Bay area, I was able to stop by the Tigo Energy offices in Los Gatos, CA and visit with their very pleasant marketing manager and ask many questions about the Tigo Energy Module Maximizer (EMM)

The EMM is a very simple device which clip on the back of each solar module.  The power leads of the solar module are connected to the EMM.  Separate, and different, leads daisy chain from one EMM to another.  Each EMM has a built-in thermocouple.  The EMM essentially insures that the voltage output from the solar module is kept high enough to prevent series degradation.  Without the EMM, a solar module in shade would develop a high resistance and seriously degrade the entire series of solar modules.

Each maximizer communicates with a central Maximizer Management Unit (MMU).  The MMU can be used to control each EMM (to enable or disable one, for instance).  The MMU also collects:

• the performance and temperature of the solar module attached to each EMM,
• solar radiance information from a separate (optional) pyranometer, and
• AC power generation from the inverter (also optional).

The communications between the EMMs and the MMU can be either wired or wireless.  The wired version uses the DC power lines.  This option requires that the MMU be physically connected to the DC power lines at a point after the individual series of solar modules have been 'combined' into a single DC feed.  This is usually just before the individual series DC feeds enter the inverter.

The wireless version of the MMU and EMMs do not require the MMU to be physically connected to the DC feed, so the MMU can be placed anywhere within a reasonable distance of the solar modules, up to 300 feet (90 meters) away.

In order for the MMU to record the AC power generation of the inverter, the MMU will need to be mounted somewhere between the inverter and the power panel.

Availability is an issue.  Supposedly, 60 EMMs and a number of matching MMUs were to be shipped out to AEE Solar in Redway, CA this week.  I need the following:

• 24 EMMs, wired, 72" power leads, MC4 connections for the solar panels
• 1 MMU, wired, with AC metering
• 1 pyranometer (Licor)

Armed with the exact information I needed to place an order, I contacted AEE Solar's CEO, David Katz.  I'd spoken with Mr. Katz several weeks ago and he had assured me that AEE would help meet my need.  Now that I knew the parts that I needed I passed that information on to Mr. Katz as well as to our local AEE Solar distributor, Orrin Farnsworth.  That was last Monday.  On Wednesday I learned that the 'wired' versions were not being shipped yet so I called and left a message that the 'wireless' version would be fine

I haven't heard back yet!

The solar modules cannot be installed until I have the Tigo components, unless I decide to forego the monitoring, which I am loathe to do.  Nevertheless, if I cannot get cooperation from AEE Solar I may be forced to either go to a competitor (DC Power Systems) or live without the Tigo components.