Coping: A Solar Professional’s Energy Suggestions

Andrew Jennings is a wonderfully sharing fellow and long-time reader.  He’s been designing and installing solar projects for more than 12 years.  So when he offered to do a details looking at home solar for both the prepper and economically minded, it didn’t take but a second to accept.  Here’s what he sent in:

Note: George has done an outstanding job laying out the benefits and some of the specifics of using solar energy over the years. The goal of understanding and planning a system can seem daunting. With a little research and familiarity with tools, anyone can do it. In an attempt to simplify and bring some perspective to the Solar options for most people, I offer the following notes for those interested in the topic.

Lesson 101: Energy, Solar Electric Systems, Economics


This is it, the thing we all need and live on. I don’t just mean the electricity available in a home’s outlet that runs all the Necessities of Life, I also mean the energy that we use as we move through our day. Just try a couple nights without sleep and then try to move a mountain, it just isn’t going to happen. It seems much of the world is in an energy struggle, whether it’s the gas at the pump or the amount of education and drive needed to succeed to the top of the heap. If you’ve never experienced an energy disruption or power outage, it can be more than unsettling.

I’ll shed light on using solar to collect energy from out most abundant energy source, the sun.

Solar: Power

Bet no one ever told you that there is enough light striking a small area of the Southern California desert to power the entire country?

When Bell labs made the first useful solar panel in the 50’s, commonly referred to as a “Sun Battery” or “Sun Generator” the technology was quickly put to work and has now become a world-wide powerhouse of economics and usefulness.

Solar Power Uses for the Public: 3 types:

Grid-Tied Solar Systems:

The world “Solar” as is used in our marketplace and on the news, is about producing power mainly in the goal of saving money from Electricity bills, or going ‘green.’ The basic premise is that instead of buy power from a utility company, a person instead produces power for their own use. These types of systems, the most common, make electricity available to the home, synchronizing power with the Utility, and any excess power beyond the home’s use flows back to the utility for the next closest home. This reduces the amount of power a utility has to provide to their customers. During the evening, when the sun is down, the residence uses power from the utility. The measurement between the amount of power a solar system puts into the utility grid compared to the amount it pulls back out, is what’s termed “Net Energy Metering.” Basically, think of the utility as an Energy Storage Account. During the day you make deposits, during the evening take credits. The little round meter on your electric service records the difference and the company bills or offers you a credit depending on that difference. These types of systems will not function when there is no Utility power, by law.


Off-Grid Solar Systems:

This is where the slogan “Off the Grid” comes from. These systems were the first use of Solar panels. This type of system is what powers satellites in space, remote cell phone towers, weather stations, and anywhere there is no option for Utility power (or for those who want to ‘unplug’). Most off-grider’s start with a generator as their power source, but after burning costly fuel just to power a light or appliance, the maintenance of the generator, and the annoying and inconvenient sound of them, people quickly look for the better, although more expensive alternative of Solar, with batteries.

Whereas these systems can be used with or without solar as the primary power source, they’re all the same in that there has to be some sort of energy storage – Batteries. These systems vary greatly in their components and capabilities and comprise less than 1% of the solar market. There are many additional parts and equipment needed for these systems and very quickly even the best electricians run with their tails between their legs when they face one of these; solely because they don’t understand how they work. After a bit of digesting the basics, they’re actually quite simple.

Perhaps the biggest difference between Off-Grid systems and On-grid ones, are the type of inverter they use. Any local automotive store sells an inverter that can be connected to the cigarette lighter of your car or it’s battery to produce our US standard 110V Alternating Current. However, there are much fancier and robust versions of these Inverters in the solar market. Specifically, the inverters for the solar market also have battery chargers built in so that they can both produce useful power from the batteries, and also charge them from an AC power source like a generator, or DC power like that produced by Solar panels. As batteries produce electricity from Chemical Reactions of metals and are sensitive and expensive by nature, steps must be taken to not over fill charged by solar panels, another piece of equipment is necessary – a charge controller. Off Grid systems for homes function best when they lots of battery storage as our culture is used to running lots of various and large appliances. For fun, learn to read your electric meter on your Utility-connected home, and you will learn how much power you use even when you think, “I’ve only got a couple lights on.” Depending on your desired goal for off-grid systems, the cost of batteries can add up quickly. There are many who’ve ‘unplugged’ but the cost of the battery bank alone cost $40k. There are others who can do with very little energy usage, and only spent $1k. When it comes to Energy storage and power requirements, ‘load calculation worksheets’ are a must as without them, most find they are sitting in the dark, wondering what happened. Many systems have the ability to start a generator automatically when the battery power gets low, and for these clients, there is little to no difference between living on the grid or off it.


Hybrid Solar Systems: Utility Powered and Off-the-Grid, The Best of All Worlds

Hybrid systems are ones that interface with the Utility company for Net-Metering/bill savings, but also seamlessly and instantaneously provide power to the home when the Utility power shuts off. These back-up systems sit idle most of the time, with the power from the solar panels going to the home or going into the Grid for credits, but the moment the utility is absent, they provide power solely for the home from energy stored in the batteries, and from what the solar panels can provide. These systems can use a generator as a source of power when the batteries are depleted or when the solar panels are not able to provide adequate power. And like off-grid systems, the Inverter/ Charger will use power from a generator to recharge batteries if desired.



When’s the best time to go solar?

As a solar professional, I’ve talked to countless people about the industry, the equipment, the financial paybacks, and solar’s future over the years. Generally, people know little about solar other than a scientific news blip about “Nano” this or “Efficiency” that. Remember that recent rover, comet lander and satellite mission from the news? How do they get their power to operate, what does NASA trust for power? The Sun.

Where I live in California, I’ve paid as much as 44 cents for a unit of electricity provided by our For-Profit utility company. Elsewhere in the US, some people are still paying as little as 8 cents for the exact same Kilowatt of power. Have you ever wondered if our country is immune from the prices of energy going up or the purchase power of our currency going down? Perhaps you should become a Peoplenomics subscriber if you need some clarity.

I’m not into predicting the future but history has shown it’s hand, the truth is that the cost of electric energy will go up, and there are not any new hot alternatives coming to the forefront anytime soon. Remember all those new US solar companies coming online a couple years ago… well, they’re in pieces laying on the ground. Right now, according to some of my contacts, it costs less to purchase a solar panel right now than it costs to manufacture them. Combine that recognition with the reality that any purchase that includes at least 1 new solar collector (module, panel) stands to receive a 30% Federal Tax Credit (TARP funds at work) off the entire system and installation – and it’s what I call a ‘no-brainer.’ Note, this credit expires after 2016 and I’m not a tax professional. There are people out there putting new roofs on their homes, because that was part of the solar cost – because the equipment is guaranteed for 25 years, and their roof wouldn’t last that long, so it’s included in the tax credit. When I show my prospective clients the highly detailed and precise financial analysis and payback numbers I’ve calculated for them given their precise circumstances, those with moderate 10 year paybacks (when the system has paid for itself), with Return on Investment numbers well over 10%, often decline going solar – I find it funny that I usually see a new car in their driveway the next time I pass by their neighborhood. I’ve seen solar pay off as fast as 5 years for some, with ROI and IRR number at nearly 20%, it all depends on your specific circumstances, and any reputable company will charge you nothing for you to find out.

So when was the best time to go solar?

Yesterday. When the power is out or the bills are too high, Last year.

But while the lights are on, and people listen to the news that our world circumstances are improving and the challenges are fading away, I’m fine adding another couple solar panels to my roof, and saving for a larger battery bank.

Even if a set of solar panels and an inverter aren’t in your future, remember the Sun can do so many fun things for us. Perhaps get a Solar rechargeable flashlight that sets in your window and read with it at night, buy a solar sun oven and make a meal in your office’s parking lot… learn how to use the sun, for some sort of energy or another, you’ll like it.

In general, the residential solar provider are now owned by banks, with lots of schemes like their a ‘zero down lease.’ And while that makes a lot of sense from the fast-talking mouths of salesmen, don’t forget why a bank would offer such an option, because it makes them money, when instead, that security could be in your pocket.

Very General and Helpful Electric Stuff

Volts X Amps = Watts, or V=W/A, or A=V/W

Amp Hours (Ah) = The amount of energy storage at a given voltage


6Volt Battery with 100Ah has 600Watts of Power, energy storage


1500Watt Hairdryer plugged into the 110V socket in my bathroom uses 13.6 Amp 1500W / 110V = 13.6A

Voltage is Additive in Series,
Amperage is Additive in Parallel


DC wires, breakers, and disconnects should be rated 156% of their predicted/measured values

AC wires, breaker, and disconnect should be rated 125% of their predicted/measured values.

Most solar equipment will have it’s input, output, or capacities on a sticker somewhere on the product

Only expect to get 70% of the power out of any one part of your system to account for efficiency losses and de-ratings of equipment.

Helpful Google design searches:

-Voltage Drop Calculator (try to be less than 3%)

-Ampacity charts

-Wire size calculator

Simple Sample Math Problems:

Question: what size wire do I need from my batteries to my inverter, given they’re very close together, just a couple feet away. What size breaker/fuse should I have protecting that bit of wire?

2400 Watt Inverter running off a 48Volt Battery Bank
2400W / 48V = 50 Amps of current

Multiply 52 Amps x 1.56 (as noted above) = 78 Amps.

The appliance I want to run uses 550 Watts from my 110 AC outlet. How long will my 400Ah battery bank power that, knowing I should only use 50% of the battery power to help preserve their life.

550W / 110V = 5A

Answer, you should be looking for a breaker/fuse that disconnects at around 80Amps, and wires that are rated for 80A. Now go ask google for a wire size calculator, and head down to the hardware store once it tells you the answer

The appliance I want to run uses 550 Watts from my 110 AC outlet. How long will my 400Ah battery bank power that, knowing I should only use 50% of the battery power to help preserve their life.


In the field electric observations worth noting

– 12, 24, or 48 Volt Systems

Higher voltage means cheaper wire and increased power handling

Higher voltage make more efficient use of various components, like Charge Controllers

Higher voltage requires more batteries to create the 48 Volts

Lower voltage systems are more common and used in RV’s and similar.

12 appliances and electric parts are common and readily available


Lead Acid batteries need maintenance, water levels maintained, occasional de-sulfating

by running higher-voltage equalization charges.

Lead Acid batteries can be dangerous due to battery acid and explosive venting gas

Gel and Sealed batteries are expensive and have a shorter life span than Lead Acid

All batteries have specific charging parameters that differ between the various types

Solar Charge Controllers

PWM (pulse width modulated) chargers need matching and often rare solar panels to be connected to them. PWM chargers often need large wires installed from the panels due to low voltage input MPPT (Maximum Power Point Tracking) charge controller are very expensive, but efficient.

MPPT charge controller often need to be programmed

MPPT charge controllers handle higher voltage inputs for reduced wire size and more options for panel selection

– Panels (a single solar collector is properly named a ‘Module’)

Most have 25 year output guarantees

Most are made in China, Taiwan, or off-shore

Are 1/4 the price they were 7 years ago

Often come in the 30+ Voltage range

Haven’t changed much in many years, they only get bigger in physical size

– Generators

1800 RPM versions work most efficiently for battery charging but cost a lot

Propane version run clean and can have a massive fuel tank located close by

Auto start features, and push button starting are extremely helpful

Have short life expectancies as they’re only meant for occasional use, not ‘prime power’

– Mounting

It’s best to mount equipment like solar panels with industry known and engineered


Times were once brighter for solar installers like Andrew…there was not a lot of knowledge online and knowing what to get – and where to get and at what price really meantr something.  But today, online retails are undercutting the serious installers who used to make some of the money on equipment mark-up.

He also passed along this, which is important:

If things like rolling black outs, EMP’s, Depressions, Coastal events…. take place, I’d suggest a $400ish dollar investment in a ‘solar generator’ could save lives, and provide comfort. There are options already available in the 400-1800 range, but anyone handy could make one themselves.

I don’t make as big a deal about the solar power system I designed and installed here are Uretopia, because I don’t like to brag (!).  But unlike 99.5% of “prepping” websites, we really do live out in the “toolies” and we really have a pretty good solar system – and yes, it is fair to say that UrbanSurvival really is solar-powered.


Ure’s custom-designed solar system comprised of T-post verticals, 5/8” rebar for the rails, electrical conduit for the top “hinges” and 3/4” schedule 40 PVC pipe for summer high sun angles.

The whole system (when new) set me back about $22,000 in parts alone, including stacked grid-interactive inverters and big 60 Amp MMPT controllers. There is about $2,500 in batteries, involved. 

Today, you could clone my system for likely have that price due to the falling price of panels.  And it is one of the best investments (other than marrying Elaine) that I’ve done.

My sincere thanks to Andrew Jennings for contributing to a “gown-up” discussion of the one thing everyone can so at some level to reduce dependence of foreign oil.

On that note, have a great weekend…enjoy Peoplenomics tomorrow, and see you Monday.

Write when you get rich,

15 thoughts on “Coping: A Solar Professional’s Energy Suggestions”

  1. “As a solar professional, I’ve talked to countless people about the industry, the equipment, the financial paybacks, and solar’s future over the years”

    When we first decided to go solar was many years ago.. solar panels for a hundred watt panel was about 1200.00 per panel.. and the inverters.. well the good ones just weren’t available in the USA and a lot of people at the top were blocking them being sold.. today.. a panel can be bought for as little as a hundred dollars for a 300 watt panel.. and today the inverters are much smaller and you can do like some Scandinavian countries have done and buy individual inverters for each panel. ( my preference since if one goes out you still keep the power of the remaining panels to work for you)
    I bought the hype.. we put in our system and figured a ten to twenty year payback for the system.. it paid for itself in five with the excess power we saved on our normal bill we invested right into the loan.. the power company would come out twice a week for months.. the end of the first month they called and said.. you can’t have a meter that goes back.. ( they would have had to cut us a check )after several months the power company ceo came by and we talked his response was.. we didn’t think they would work this good.. and it has amazed us. I said.. why not embrace the technology. do like other countries and offer to install systems and give a percentage back.. you do the maintenance they get a cut on the cost of power and you increase your production potential.. his response.. all in all we are hear to sell power.. so instead they put up these huge billion dollar wind turbines invest in more coal fired plants..( oh even if they did invest in the solar remote units.. they would still need those plants.. so embrace all of it) and we are still being controlled by other countries and our energy needs.
    My way of thinking it is a simple process.. we invest in the future embrace the past and slowly do our transitioning to independence.. without the huge infrastructure revamping.. energy companies still maintain their grip on the public while moving gently into the next era of energy production.. I just got my next solar power generation system with the enphase inverter.. at a huge price reduction.. instead of ten or twenty years payback this one will pay for itself in one year.. now if I lived in other areas with the incentives available.. it would be just a couple of months .. that is a no brainer if you ask me.. but then it isn’t like a car or a new chair.. you really can’t touch it stroke it or oogle over it.. you turn on a lamp and say.. lookie that.. no big what.. but when the power is out and you can pull out a cold one.. now that is something to oogle at..

  2. Mr Jennings article is quite informative, however he must have missed the fact that the Consolidated Appropriations Act, signed in December 2015, extended the 30% expiration date for PV and solar thermal technologies to 2019, and introduced a gradual step down in the credit value for these technologies. The credit for all other technologies will expire at the end of 2016.

    • this is wonderful that is important for my area we don’t have a lot of incentives for going solar…. LOL that means my three thousand dollar system will be two.. phew..

  3. I am grateful for your suggestions. I bought a 6k system 5 years ago that is grid connected. It is installed on the ground. Every time I am above my ‘safety reserve’ I put an extra 1k pay off on my mortgage. Thanks-Karen

  4. Well written article. As a fellow solar energy professional, I would just like to add that you should properly add in the cost of replacing your inverter every 10 years. It is a little known fact, but not a secret as it is openly discussed by the inverter OEM’s, that inverters are only designed with a 10 year life expectancy. It is therefore no coincidence that they commonly come with a 10 year warranty. There are some really good resources available at NREL if you want to follow up.

    • don’t forget to tell them to buy extra fuses.. LOL I had one stop working on me it was well over ten years old.. figured well its about time.. I bought an extra had it switched out only to discover it was a fifteen dollar one amp six hundred watt fuse.. go buy fuses tape them to the inside of the case..

  5. Your ground based array is impressive. Is it possible to post a picture of the back side of the panels so we can actually see the mounting? Did you drill and screw the panels? Did you clamp them? How far from the actual panels to the battery bank?

    I’m considering setting up an array on a trailer for greater flexibility, complete with all electronics and batteries. It also needs to be designed for up to 100 mph winds and gusts here, since there are no tall trees. The trailer would normally reside out of sight and blocked for stability, and feed a standard transfer switch with no grid feed.

    • sun elec and wholesale solar both ship with the mounting brackets and roof mount.. back in the middle seventies before they sold the old c band satellite dishes I had seen one a guy had mad so I build a satellite reception center for myself LOL.. ( never again blew 4 TV’s up trying to convert them to a testing equipment ended up.. doing the can you see anything now.. adjust.. how about now adjust.. LOL sucked.. then if your a sixteenth of an inch off from eyeballing it. your are well over five hundred miles away from the satalite.. so once you did get a ghost signal.. it was up down side to side to find the satalite.. LOL LOL LOL LOL LOL memories.. and the dish.. chicken wire and window screen LOL LOL oh god the days of youth)with frameless panels.. some either frame them or glue them down.. LOL.. cheaper to just buy the frames.. anyway.. the reason for that story is I hear young people say I will make them.. no go buy one made and tested and say god didn’t I get a good price on this and for what fifty cents a watt you cannot make one for that price..

      • I did some research on this yesterday and designed a simple rack that I can weld up out of angle iron and rectangular tubing. It’s rigid, and Unistrut can be used to make channels for clamping panels in place. The entire unit can be moved using a forklift or tractor, and can be bolted to a trailer with batteries and inverter for portable power. The rails sold by the major solar providers look good but are way overpriced compared to Unistrut which can be bought in 10′ lengths at the local Home Depot.

  6. I have used solar for hot water for decades, and for electricity for perhaps 5 years. The water heaters I used were cast offs from the 1970s, but the electric is top of the line, modern stuff.

    Some observations: battery tech is currently undergoing a Renaissance, so spend a little more to get a small, but scalable battery system may be really helpful in a few years. A few years ago there was a terrible freeze here that exceeded local design limits, so pipes broke, houses were cold and the grid was overtaxed. I only discovered that we had beempn in a 6 hour blackout when I tried to run the dishwasher. In fact I was muttering angrily that it was only 6 months old when I realized the lights, water, TV, computers, fireplace insert fan, refrigeration, etc. we’re all on the solar side, but the dw wasn’t. Strange feeling, that. My neighbors were freezing in the dark and I was unaware of the problem.

    Next item-Solar hot water may have a better return than electric, especially in sunny places. My ancient panels finally broke this year and my propane consumption has skyrocketed. Health issues have dueled replacing them, but it will happen. Not having to earn money is better than having a job, sometimes.

    My utility put a new meter on my system, and my electric bill went up $60 a month. Then I discovered that their new meter allows them to pay me less for my electricity than they charge me. The difference is that they include the cost of the grid in my bill, but only pay me the saved cost of energy. So my next tricks will be to schedule consumption during peak sola gain times, like well pumping into a holding tank, running the dryer, cooling the house down, and, maybe, even putting a freezer on a timer.

    In Texas there is no property tax on solar and rainwater collection, and no tax on the output, yet these are part of the Homestead, protected from most creditors.

    If you have money in a retirement account, subject to tax on withdrawal, the 30% tax credit probably neutralizes the taxes. So you can take some money out of the casino and turn it into tax free income, plus energy insurance. If you add water harvesting, storage and pumping to the mix, your home will continue for decades to be usable, with little or no utility help.

    Let us suppose we compare solar plus rainwater to a rent house. The rent is taxable, and the rent house is subject to propert tax. Likely it has much higher maintenance, and you rely on the tenant to pay you. If not you still have your costs. In a bankruptcy or debt situation, the rental is subject to seizure by creditors. Plus you either pay for management, or it is a part time job.
    Contrast to solar and rainwater. Tax credit for solar. Free money. O tax on the output. Yet. Arguably lower maintenance. Take the avoided costs of energy and water, and add your income rate. That is really how much you have to earn to break even. So you save money for something else, and/or work less. If your job goes, and your homestead is paid for, in Texas you only need property tax money to live. Which can be deferred in old age here. Plus you have more security, refrigeration, hot and cold running water, operable computers, TV etc, medical device power, etc.

  7. what type system do you have that you estimate can be duplicated for approx. $12000. thanks, hope your eye problems are about over, some of it was frightening to read about. I will wade thru the archives before I ask about your hydrophonics setup. thanks, pat

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