Friday, January 19, 2018

Keeping it Neat: Off-grid Samlex Inverter Installation w/ E-Panel

Chuck finalizing the installation of six SolarWorld 300W solar PV modules.  The Samlex EVO4024 and battery bank are housed inside this nice pre-built shed.

Samlex wasn't even on my radar until I got a call late last summer from a couple who had purchased a Samlex EVO4024 inverter for their off-grid home near Belington, WV.  Up to that point I had mostly used Outback and Schneider/Xantrex brand equipment for off-grid jobs.  Chuck and Deb who had this Samlex unit had also purchased a bank of Trojan batteries and a Generac 15kW EcoGen generator.  When they called they were in search of someone who could pull all the pieces together into a functioning off-grid electrical system.
Part of pulling the pieces together was the addition of a MidNite Solar E-Panel.  Not to get too technical about things, but I find it's common for folks who source their own equipment to overlook key switch gear and enclosures that ultimately make a system safe, serviceable and code compliant.
Looking at the EVO4024 for the first time I was cognizant that the unit, as it is sold, could not alone yield a polished final installation.  Basically, it was lacking a cover for the large DC cables that connect the inverter back to the batteries.  This is fairly common among inverter manufactures, but does not yield a safe or code compliant installation (it also leaves things looking sloppy).
Many off-grid inverter manufacturers offer units without any enclosure to protect the DC cabling.  Most, however, do offer an optional enclosure that can be purchased separately and is purpose built to be paired with their inverter equipment.  These optional enclosures commonly include space for disconnects and breakers that protect the wires and the electronics in the system.  Samlex does not offer something like this and I was a little perplexed after I first gave their website a once over and concluded that I would have to look elsewhere.

The big dark blue box is the EVO4024 inverter.  It is mounted to the E-Panel which is affixed to the wall.  The MidNite E-Panel includes the gray portion below the inverter (this limits access to those DC cables).  The small black "thermostat" at the right is the control panel for the inverter.  The larger black piece of electronics is an Outback FM80 solar charge controller.

MidNite Solar would win an award as the most creative manufacturer of solar related enclosures and electronics equipment.  They were the next place I looked for an enclosure that could be paired with the EVO4024 inverter and sure enough they had something tailor-made to fit!  MidNite Solar has been manufacturing E-Panels for maybe almost ten years - I can't remember for sure.  These E-Panels were created as a way to minimize the footprint of an inverter installation as well as the cost.  I don't always use E-Panels because the wiring space can get tight, but they certainly have their place and they are the only game in town if you want to make a Samlex EVO4024 installation safe and sharp looking.

This series of photos is probably a better illustration of how the E-Panel consolidates the AC and DC wiring as well as the associated breakers.  Note the big red breaker guard for the main DC cables on the left side of the E-Panel.

My experience with the Samlex EVO4024 was great.  The unit has a very nice relay that allows it to trigger the EcoGen generator to fire up automatically without the addition of any other electronics  Another plus for Samlex is the comparatively low cost of the system control panel.  The cost of inverter control panels has become a major hang-up of mine.  Some control panels cost more than $400!  That's a chunk of change for something that really resembles a beefed up thermostat.  Anyway, the controller for the EVO4024 costs less than $200.  It's probably the cheapest controller out there.  Finally, and most importantly, the technical support from Samlex was the best I have had from any inverter manufacturer.  By "best" I mean that there was no time wasted on hold and the support staff gave me the impression of being upper-tier right off the bat.  The technician who I spoke with was knowledgeable, polite and I got my questions answered while I was in the field.  I called multiple times and there was no deviation from this stellar service.

Monday, January 15, 2018

Winter Sun | High Voltage

Well it's January 15 and you can already tell that the days are getting longer.  The cold temps have conspired with a few really beautiful sunny days to make for some good peak PV power production.  Those bluebird days where the snow reflects the sun and the temps stay well below freezing are some of the best days for solar.

People are often surprised to learn that colder temps really enhance the output from a solar PV system.  In fact, cold temps are a primary consideration when designing a system.  The voltage from a solar PV panel can increase 14% or more as the temperature decreases.  If you fail to account for this during the design of the system you may goose the charge control or inverter equipment with a voltage that exceeds the operating limits.  Yikes!

It being winter, I like to roll out my mother-in-law's favorite ski video.  So far, this winter has already bested the last two for quality skiing days.  Hope there are many yet to come this season.

Wednesday, July 12, 2017

What Happens When You Shoot A Solar Panel???

I don't do as many educational events as I used to.  But, speaking to groups about solar energy occasionally did put me in the position of trying to field questions about solar panel durability; you know, hail, wind, bullets. 
There was often some jackass at the back of the room who would ask, "What happens if you shoot 'em?"

Like a lot of stuff, solar panels break when they are shot.

The warning signal at the Randolph/Pendleton County line on U.S. 33 between Harman and Seneca Rocks was disabled by somebody abusing their Second Amendment right several months ago.  Recently I noted that the shattered front glass on the module had weakened enough that wind was able to blow the entire assembly out of the aluminum frame. 

The sandwich of materials has pretty good adhesion even after being blown out of the aluminum frame.  By "sandwich" I am referring to the glass on top + silver circuits +  dark colored solar wafers + white tedlar backing.  The glass provides protection for the silicon wafers and circuitry that you can see above.  Most solar panels have glass that is rated to withstand the impact of 1" hail at 50 mph.  The glass accounts for the rigidity of the solar panel and much of its weight.

No more warning lights.  The blinking lights were powered by the solar equipment.  This is a no-joke descent with several hairpin curves and a couple of shear drop offs. 

Wednesday, May 3, 2017

Honey Factory in Job, WV

Busy as bees......
These hives are the property of a new distillery, Still Hollow, that's undergoing construction in greater Job, WV.  Listening to the buzz from the sun warmed hives makes me think a bit about the frenzy of electrons  moving through a solar PV panel on a bright spring day!

Wednesday, April 26, 2017

Passivhause Solar PV: Garrett County, Maryland

Homeowners, Bill and Fran, opted to add solar PV as part of their new home.  They elected to build the house to a rigorous Passive House standard to minimize the energy footprint of the home and ensure that their new home would be comfortable and inexpensive to operate.

The 9-kW solar array is made up of thirty SolarWorld 300W modules.  The solar modules are mounted to the standing seam roof with S-5 clamps which eliminate the need for drilling through the metal roofing material.  SMA inverter equipment converts the DC power from the solar to AC which powers household circuits and turns the utility meter backward.   Special thanks to Larry at CHIPS Network for his help with connecting the inverters to the world wide web.  Production data like that shown below (sunny day in April!) is uploaded and stored on the SunnyPortal website.

Friday, January 20, 2017

"Webster couple improves off-the-grid living with small-scale hydropower" - Charleston Gazette

Micro-hydro in West Virginia gets a headline in the:

Great article in Thursday's Gazette about the Janowski's hydro system in Webster County, WV.

Dave and I didn't make it into Rick Steelhammer's article so I gave us a little space here on the blog, although I think we're both a bit camera shy.😀  That's the ES&D turbine in the background that provides most of the power for Mickey and Jenny's off-grid home.

Home Power Magazine also featured the Janowski's home in their July/August 2015 issue.

Thursday, December 15, 2016

Grid-tie Solar Power System with Battery-backup in Beverly, WV

Sixteen SolarWorld PV modules back-feed power to the electric utility during normal operation.  During an outage the battery bank and electronics in the basement supply power to selected critical loads.  The battery bank has eight large Trojan deep-cycle batteries.  The backup system can supply 21 amps (240V) and the stored power is close to 17 kWh.  In a prolonged outage the solar will help charge the battery bank as though the home were off-grid.