John’s Rants

John’s ranting about the shortage and price of solar modules over on his blog. He can get pretty entertaining at times, but he is also very serious. This guy wants everybody to have a roof or backyard full of solar panels.

I find it amazing that the government creates a full tilt initiative to promote solar and then puts all kinds of roadblocks in the way. It must be working to some degree. We know solar farms are going up everywhere, but even in the home and DIY market, it is getting harder to find 24 and 48v system hardware. Closing down reliable coal and nuke plants before the solar farms are running all get battery assistance is really dumb, especially with electric cars being forced upon us.

Then, once people adopt solar, they find the .gov or the power company has put some limitation in the way. California now requires every new home to have solar, but they have been promoting a rate structure that would eliminate solar. In the meantime, people in California need solar to keep the lights on, because the power company can’t seem to do so.

Good news on that front, a judge just ruled that Arkansas power companies must go with net metering and pay homeowners full retail for their excess power. Even better, no solar connection fees.

There is also potentially good news on the solar panel front. The industry notes that many solar farms will be repowering soon. The hitch is, THEY have to find some new solar panels. Nothing wrong with second hand solar. I have over 300 of them, 15 years old, out on the Solar Shed and my house is off the grid. These were not even pampered like farm solar panels. These were stomped on and thrown off the roof.

When John sells used, they are tested and graded by appearance and you get a warranty. It may soon get better than that. So many panels could be coming to market that there will be new uniform standards for grading. For example, today’s panels are made with higher dielectric ratings (how high a system voltage you can run without you getting electrocuted ) Early grid tie strings would run up 300 to 600 volts and now the commercial farms can run over 1000. That’s good to know if you put together a grid tie system with a new inverter and used panels. (Unless you live in Arkansas, grid tie may not be a good idea.) I think the rest of it is pretty much what John has done for years.

There’s my fantasy. Piles of solar.

Anyway, we may see cheap panels return IF the solar farms can get new panels. The used panels will not be these 400+ watt super modules, they’ll be the 250 watt modules. No problem, you pay by the watt and not very much. Just use more. Those 300+ solar shingles at the Solar Shed are only 34 watts each on a good day, but they add up to some serious kilowatts.

Now, if we could only get rid of a couple of dozen government agencies that nitpick us to death! Seems like I recall that in Biblical times they’d have a Jubilee. Every 50 years, everything would get reset. That’d be great. Congress can crank out a lot of laws and regulations in 50 years, but at least they would not pile up on the previous ones.

In the meantime, let’s get John outfitted with new boots and fedora. Send him out to search the land for more panel bargains.–Neal

There’s An App for That

In early summer of 2015, I was on my solar expedition launch Sun King. Cruising up the Tennesee-Tombigbee Waterway. It was raining and getting dark as I approached the lock and dam at Aberdeen, Mississippi. I don’t like to run in the rain and there are limitations to running in the dark in a solar-powered boat. Nonetheless, I pressed on. I had a rendezvous the next day. An important one. My wife and Mom were bringing supplies to restock my chips and jerky rations.

Getting through the lock was no big deal, but it was raining pretty well by the time I cleared. I turned to starboard and went looking for the channel markers to the Aberdeen marina. It turns out the LED floodlight was inadequate and the rain made it impossible to find the way. It is tricky in good weather if you are a stranger. I found a shallow spot and dropped anchor for the night. After supper, I heard a power boat go by. Local river rats always know the way.

It was a good thing I locked through when I did. By morning, the river was up 20 feet and the current was faster than my boat. Man, it had really rained. It was still gloomy, but after breakfast and coffee I wound my way through the channel and found the marina. It was still a little wet, so I tied up at the seawall to wait before checking in with the folks who ran the place. Note that despite running in the dark, fixing supper, fixing breakfast and getting underway in the gloom of a rainy morning, I still had plenty of power.

Tech specs: 1620 watts of solar panels, 6x Energizer 8v golf car batteries, arranged series-parallel for 350 ah at 24vdc. 8 kw inverter (overkill, but the 3kw I had before had died). Motor was a custom build, based on an array of Minn-Kota parts.

After 4 days of cloudy weather, the batteries may be getting low in your solar power system. Try cutting back on the loads as the panels will charge, even on a cloudy day. This day, I fixed a cup of coffee and went beach combing along an island shore in Tennessee Lake.

It would be a while before the resupply crew would arrive, so I reclined my captain’s chair and settled back for a little snooze. It had been an unsettling night with all the thunder and lightning going on. My nap didn’t last long as suddenly the gawdawfulest blast of catterwallin’ occurred and just kept on.

Mississippi has a network of storm sirens throughout the land. You can hear them for miles and if you are between them they set up something of an echo. I had tied up right under one of these infernal devices. What a rude awakening!

I survived that day at Aberdeen and the various perils of the entire 1920 miles of the trip around the big island of Mississippi. Bet you didn’t know Mississippi was an island did you? If you can drive a boat around it it is and I did so. So it must be an island.

Yesterday morning I had a jarring awakening. My phone has somehow developed the ability to be the equivalent of a Mississippi tornado siren. It doesn’t matter what the volume settings are on the phone, this makes itself heard. Yup, tornadoes inbound. I checked the radar and saw it was doing the usual split up the river that is our county line and the other river that is our state line. I don’t know why, but the tornadoes like the river valleys better than our ridge. I’m ok with that and I rolled over to catch some more zzzzs, while Pensacola got thrashed.

Later I got to thinking about phone apps that might be useful for solar. Since I have gone fully off grid, the days of endless gloom and rain have begun. I have been going through some neglected areas of my system to try to squeeze out a few more watts.

At the planning stage, I found Suncalc which shows the sun angles at different times of day and in different seasons. If you can’t site your solar panels to the traditional south orientation, Suncalc might help you find a good alternative.

At the building phase, there is a app that lets you use your phone as a level or clinometer. Note that not all phones have a sensor array. I hold on to old Androids to use as tools if they have sensors my regular phone does not. If you can play video games by tilting the phone, you have the sensors that will let you mount your supports vertical and horizontal and then set the panel angles.

Some phones have a magnetic sensor that will drive a compass app to select your direction of the array. If you don’t have that, some compass programs will work with the GPS in your phone if you walk around a little.

There are also a number of apps to predict your solar insolation or available sun power. Some are purely theoretical and some are somewhat interactive. Solar Radiation Calculator decided that at my location I should receive 2920 kwh per year, per square meter, from the sun. Given that panels in perfect alignment are good for around 20% efficiency, I need a number of square meters. That one is probably best for the planning phase. Another app i tried, PV Solar Forecast, scans weather service radar and cloud maps to guess how many watts your system will give you. I am still learning this, but it looks like it is assuming you have a grid tie system. There are some calibrations available, so this one might be useful for rough estimates of the day’s performance.

Not a lot of watts, today. We should catch up over the weekend.

Now, for even more accurate info, you will find there are apps that will talk to your charge controllers, inverters or grid tie system to get the direct scoop on things. There are even aftermarket wattmeters that your phone can monitor with Bluetooth.

Try roaming the Apple and Play stores for apps. Usually, there are free ones you can try. These often come with reduced features and annoying ads. If you find an app you really like, paying a very few dollars can make those ads go away and bring you some new features.

Let’s see now, earlier, the app said I was making 400 watts. says I have perked up to 1.6 kw, and by the end of the day as the rain clears I’ll still have clouds and low output. Not a good solar day, but I already sort of knew that. Looks like tomorrow will be better. Good, my batteries need those kilowatts.

—Neal

GS 4048 Hybrid inverter

Louisiana Screws Up Net Metering

Don’t Worry, We Can Fix This

After Hurricane Katrina, solar power took off in New Orleans. Long nights without power left folks wanting a little more control of their situation and rooftop solar took off.

How much of that was actually usable when the grid is down and how much was grid tie? I’m betting there was a lot of grid tie.

Nothing wrong with that, especially if you get real net metering. Figure up all the power you made and how much of a net surplus or deficit you had and money changes hands at the retail rate. In other words, if you used 1000kwh (kilowatt-hours) of grid power and the rate is 13 cents, then you sent the power company a check for $130. If you made 1000kwh more than you used, then the power company sent you a check for $130.

This is a really sweet deal, if you can get it. A few weeks ago, the Show and Tell post featured a Texas system owned by Daryl and some add-ons to a South Carolina system owned by Courtney. Both have that deal. Apparently, Louisiana has had that deal and now they want to change it. So much for the payback calculations.

I’m just going to use some round numbers, here, but they’ll be close to the real deal. Under the new deal, that begins with the new year, if you use an extra 1000kwh, you’ll still pay $130, but if you make an extra 1000kwh, you will get $34, based on the wholesale, or “avoided cost” rate the power company pays.

Ok, it’s actually worse than that. If your system makes an extra kwh today, you get your 3 pennies credited, but then tonight when you use a kwh to watch the evening news, they are going to charge you 13 pennies for the electricity they bought from you for 3! It cost you a dime for your own power! Figure, too, that a lot of power companies have extra connection fees for solar producers.

This puts you where I am with my power co-op. Florida law has been that the “regulated power provider” has to do net metering. As a co-op, however, they are exempt, so they make it foolishly expensive to connect grid tie solar.

Fret not, my friends, for there is a way for you to have your solar AND keep the lights on after a storm. It is called HYBRID solar. You will probably have to reconfigure your solar strings and buy some more gear, but what you will end up is not only a more versatile system, but one that makes more economic sense, as well.

If your grid tie system is in the most basic form, you have a number of solar panels in series connected to a string inverter. If this is your system, you remove the Sunny Boy and separate the seriously high voltage string(s) of modules into groups of, say 3, to get the voltages you need for charge controllers. Yeah, you gotta buy charge controllers. Maybe you only need one if you get the monster 300 amp Flex Max.

The output of the charge controller(s) goes to your new battery bank. The size of your battery bank is going to depend on how long you want to keep the lights on with solar power. If you have a lot of solar and a little bit of battery you can cook the life out of the battery in a hurry. A Flex Max can be turned down to accomodate the battery’s well being, but then you aren’t using all of your solar. I know it hurts to write that check for a big battery stack, but you won’t regret having it.

Now, you need a hybrid inverter to replace your string inverter. If you were doing your grid tie connection via a hybrid inverter to start with, then congrats. The “hybrid” inverter is called that because it can do grid tie, it can act as a standalone inverter, it can act like a UPS, it can charge batteries and sometimes they have other tricks.

Outback GS 4048A
Outback GS4048A

I’ll tell you how you need to connect this new hybrid inverter in a moment, but you need one more thing. You need a transfer switch. This allows your inverter to connect to SOME or ALL of your house’s circuits. The simplest thing is to use a whole house transfer switch, which of course may cost more and will require that your new hybrid inverter be hefty enough to handle all the loads. You may think that you can pick and choose what you have running to stay within the inverter’s capabilities, but you will likely have someone in your house (I’m not mentioning names) that will want to live his/her life without limitations on the power they use. Count on it.

Otherwise, you can use a transfer switch, such is commonly used with backup generators to run power to essential circuits, leaving the clothes dryer and electric range out of the loop. These switches are cheaper and readily available but may present logistical issues, depending on where your main power panel is.

For a couple of examples, Tom has his whole house switched to the output of his GS8048 inverter pair. One didn’t quite handle it all, but the GS series can be paired for twice the output. With 16kw on tap, he doesn’t have to worry about running anything or everything, saying he has only seen the load go up to 10 kw. If one of GS8048s should fail, he can proceed with care on the other one until the bad one is repaired, but he’s never had a problem with either. He also has a power line connected to the input of his inverters. This is like a giant version of a UPS (Uninterruptible Power Supply) with the switches so set. Change the switches just a bit and the inverter is providing power to the house, with the grid on standby.

During the day, when there is plenty of sunshine, the batteries charge, the a/c cools (his setup has enough reserve power that the a/c starts without a Smart Start), the computers run, the fridge cools, etc. Nothing is going to or from the power company. There is no grid tie meter or agreement with the power company, so make sure the inverter never gets switched to “sell” mode. These modern smart meters will tell on you!

To minimize the load at night, baking and laundry are done during the day. Come night, the modest battery bank gets well into the evening before the inverter decides to switch back to grid to save the battery. The rest of the night, Tom pays his 13 cents for every kwh he uses. Overall, he doesn’t ever buy any of his own power at a markup and he for pay a lot of the bought kwh.

Tom has plenty of solar. By backing off on his nighttime a/c or investing in a bigger battery, he could probably eliminate his grid consumption altogether. He could keep the grid as his virtual backup generator or just give the power company the one-finger wave goodbye.

On my hybrid system, I don’t have the whole house connected and I don’t have one of those fancy interactive inverters. My transfer switch connects my inverter to the circuits you’d want if the grid goes down and a bit more, within the capacity of the inverter. The sun makes the power and I use it to run the freezer, two fridges, home entertainment, computer/internet, microwave, coffee pot etc. And the a/c. And the farm jalopies. There is no grid attached to the solar power system, so consumption has to stay within production. This is mostly determined by how much the a/c is used, as there is much more than enough power for everything else.

I’d use more of the kwh I produce if I had a bigger battery and inverter, but there is no charge for a grid tie connection and no paying out dimes for using my own kwh.

If you are new to solar, consider a hybrid system for both savings and power redundancy. If you are on grid tie and are or will be getting a raw deal, then consider converting to a hybrid system. Sun Electronics should have pretty much everything you need to make the change at a decent price and they back the stuff they sell. –Neal