Thursday, November 8, 2012

Self-Sufficiency: I Am Afraid It Is Necessary

It looks to me like there is a real likelihood that we are going into a another serious recession next year.  For all the "soak the rich" rhetoric Obama was throwing around, he knows that even at a 100% marginal tax rate on the $250,000 per year crowd, it would only make a small dent in these outrageous deficits.

More importantly, these are Obama's supporters.  (He won eight of the ten richest counties in the U.S. -- and by larger margins than the rest of the country.)  The increase in marginal tax rates is a dodge; actual increases in taxes collected from this crowd will be negligible (which is why Boehner is emphasizing eliminating tax loopholes as a method of increasing revenue -- and why Obama will never allow that).

Increased taxes are going to be hitting the middle class, because that is where the money is.  More importantly, as employers shed workers that take them above the 50 employee threshold for Obamacare regulation, a lot of people are going to be losing their jobs.  Many of them, of course, voted for Obama, and are going to be surprised that it won't matter that they get free contraception paid by their employer, because they no longer have an employer.

I am concerned that as the economy worsens, we could actually get something that is nearly unheard of in American history: food riots.  Being able to grow some of our own food to supplement stockpiles seems like a good idea.  Neither my wife nor I are really gardeners, but the time to learn this is now, while food is not in short supply.  We'll be building some raised beds come spring.  The native soil around here is not very impressive, so we'll have to bring better soil in for the raised beds.  I do wonder if planting legumes in the native soil for a couple of years might be a good start, however, because legumes nitrogenate the soil.

Far less likely on the list of concerns -- although much more than it was a week ago -- is the prospect of nuclear terrorism in American cities.  At some point, Israel is going to have to destroy Iran's nuclear weapons program.  This is likely to be only a temporary delay, unfortunately, and when Iran does start production, I would expect that within a year or two, nuclear weapons will either be used or threatened to be used against American cities as part of a blackmail effort to get us to stand by and allow Holocaust II.  Most of the European governments will wring their hands about how terrible this is, but that's about all.  Obama probably won't do much more than wring his hands, and the threat of losing a couple of our cities will give him the excuse to do what he would do anyway.

For that reason, I am still very interested in being at least partly independent of the electricity grid.  One of the major cost problems with any low-end solar power system is that you need the following components:

1. Photovoltaic panels: still too pricey to make economic sense, even with tax breaks, for just producing your own power, but when you do it for energy independence, not so silly.

2. One or more deep cycle batteries to carry you through the night and perhaps, with enough batteries, through two or three days without sunlight during a bad storm.

3. An inverter to convert the 12 VDC batteries to 110 VAC.

4. A transfer switch so that when you are running your solar panel/battery/inverter setup, and the grid is out because of storms or incompetent politicians, you don't send power out and zap some Idaho Power lineman.

It is possible to buy items 1, 2, and 3 relatively cheaply, especially if you start out small for experimentation.  You can add more panels over time to increase generating capacity, and add more batteries to increase storage capacity.

The inverter is not too bad on price -- but as your capacity increases, your inverter has to scale up.  (And since you are going to want to run electronics off these, you need pure sine wave output inverters, and these cost more.)  This is one of those places where you start small and step up, but each step up is expensive.  I'm not sure that there is any way to reuse several small inverters, except by creating effectively several independent power systems for different circuits in your house.

The transfer switch is the single big issue, not because of the price tag (although again, this is a matter of scale) but the problem of installation.  This is something that I would hire a professional to do, because of the legal responsibility if you do it wrong, and the risk to self and property.  But the price tag for a professionally installed system comes to several thousand dollars, and there does not seem to be any way to get this price tag down for a starter system.

But it turns out that the backup generator that we already have has a transfer switch on it.  When we lose power from the grid, the backup generator (a Generac brand 7 kw model) turns on after a few seconds, and the transfer switch prevents power from going on to the grid.  I have a suspicion that all I need to do to make a low-cost, do-it-yourself photovoltaic addition for an experiment is:

1. Photovoltatic panel. ($240)

2. Deep cycle battery (35 amp-hour, sufficient for testing): $70

3. Pure sine wave inverter (600 watt, sufficient to test the concept and even a bit of buildout capacity): $195.

The only other thing that I need, apparently, is a power cord from the inverter's 110 VAC output to plug into a house outlet.  This feeds electricity back into the at least the circuit that outlet is on -- and perhaps it will feed back to the rest of the circuits on the same breaker panel.  If this is not the case -- if the power will be limited to the circuit for that outlet -- then it might make sense to have several independent inverters drawing from the batteries, and feeding different circuits.

There is one other possibility, and that would be to have the electrician that installed this generator look at what is required to provide inputs to the breaker box from a homebrew solar panel.

UPDATE: Thanks for the helpful advice.  It appears that I will need a secondary transfer switch between the inverter and the rest of my system, and so I will need an electrician.  This might be part of the solution: a combination inverter/charger/auto transfer switch:

Auto-Transfer Switching for UPS Operation
When the APS750 is connected to an AC power source, power is passed through to connected equipment and the battery set is charged via a three-stage, 20-amp charging system with adjustable settings for wet/gel battery types. In the event of a power failure or severe voltage fluctuation, the APS750 responds with a near-instantaneous (16.6 millisecond) automatic transfer to battery power. Any number of user-supplied batteries may be connected to the APS750 to provide extended battery backup support for critical equipment. A three-position switch enables you to select AUTO mode for automatic transfer between utility and battery power, CHARGE-ONLY mode to maintain a full battery charge with no automatic transfer switching when the APS750 is connected to AC power or SYSTEM OFF mode.

12 comments:

rfb said...

Clayton,

You can obtain a manual transfer switch for much less than your quoted "thousands". The Ronk 7215 (http://www.ronkelectrical.com/meter_rite_gl.html) sells for $530 (http://kenstansbury.com/transfer-switch/)

I use the 7416 model and it is a quality piece of equipment.

With a manual Tfer, you operate it during a power failure instead of the automatic activation of the switch, but it is simple, effective and safe.

Anonymous said...

In my rual area there is a cut off switch on the meter box that the electric company requires for all new installations or upgrades. They also do the final hookup and inspection before turning the current on.

Alien said...

Since you'll be using the services of an electrician, you might want to consider adding a circuit or two to the transfer switch circuit panel.

One circuit in each room connected to the transfer switch panel provides backup power (however that power is produced) to each room. I just finished rewiring all my ceiling fans and attached lights into one circuit and adding another circuit with one receptacle in each room to the box.

Backup for me is a propane-powered generator, but I'm also looking at PV panels, in particular a multi-year phased approach to get to the size system I'll need.

RE: the inverter business - I haven't looked for one so it might already exist, but an online PV forum that connects PV users might offer a market for the used, smaller inverters as some users upgrade to larger ones and new users begin creating systems.

Rick C said...

Clayton, any inverter designed to be used with solar panels in a grid-tie system should have built-in islanding capabilities to protect the grid from being charged by it. I don't know that it would necessarily be listed in the blurb on Amazon, though. I remember seeing articles about it back when I was reading magazines like Home Power.

Stan Burton said...

What you describe is a "suicide cord". But do NOT do that. It does not eliminate the need for a transfer switch because you are sharing the leg with the generator. You need a secondary transfer switch.

Clayton said...

Thanks for the helpful advise. I does seem as though I am going to need to engage an electrician no matter what I do.

dearieme said...

Legumes: don't be surprised if you find that some flourish and some don't. We can grow beans well but not peas. We asked a local seeds nursery firm about this: "we find the same" they replied.

P.S. Can you get seed for Borlotti beans in the US? They are delicious and, free gift, beautiful. We are also great fans of broad beans.
http://en.wikipedia.org/wiki/Vicia_faba

Windy Wilson said...

As for the poor soil, didn't Viscount Townshend ("Turnip" Townshend from British History)recommend turnips? If I remember, turnips and potatoes were also good for the soil, also fixing nitrogen in the soil and allowing the prosperity of grains where previously only browse and forage would grow.

DOuglas2 said...

I'm seeing this stuff about 100W panels, 600W inverters, and then "perhaps it will feed back to circuits on the same breaker panel" and I'm deciding that I don't understand the concept here.
If you are very judicious when reliant upon the solar power of going around and unplugging everything with passive draw, and using the shutoff disconnect on everything that is permanently wired, then I suppose trying to power the circuit panel with hundreds of Watts will work. They key is to keep the sum of the loads that you want to use simultaneously under the capacity of the inverter.
If you will get an electrician involved, I'd think bout the following (if it hasn't already been done with your backup generator):
Plan out what things you would really want when disconnected from the grid. The well pump might be top of the list, and any gas or oil appliances that require mains electricity for switching. Have these circuits moved to an electrical "subpanel", and then have a manual or automatic transfer switch between that subpanel and your main panel. Size your inverter for the load you need, and start building up panels and batteries as budget allows.
Keep in mind that solar panels are giant sails that need an extremely firm mounting for when wind is high, and that the output of each panel, although low in voltage, can be quite high in current, so the size of wire and security of connections is very important for safety from shock and fire.

Anonymous said...

My system is solar panels that feed power to the grid when the sun shines, and draw power back at night.

Basically I am selling power to them, and they sell it back at the same cost, and if I don't generate enough, I pay, if I generate more, then I get a credit (it doesn't make sense to cash it in, since they only pay wholesale for any extra I generate) So my electrical power bills are pretty much paid from now on (PV panel life is guaranteed to produce at least 90% of rated capacity for 25 years.)

The drawback to this, is that if the power goes out, I have no stand-alone capability. I suppose I could hook up some jumper cables to the feed from the panels and do some arc welding, but I can't use 28 volts to run the TV or Microwave.

The upside to this, is I don't have to store or maintain batteries - checking water levels, etc.

All in all, I am not independent of the grid, which is not a major drawback in town, since our power is pretty reliable - maybe five outages in the last 5 or ten years - usually coinciding with a winter storm.

Alien said...

@Stan Burton -

Would the problem you describe be resolved with a "three position transfer switch"? All the transfer switches I'm aware of have A-B positions; do you know of any that will do A-B-C? Otherwise, I don't see a way around 2 transfer switches, as you point out, both of which would require a disconnect switch (if the transfer switch automatically (or manually) goes to generator when the grid fails, house circuits are connected to either grid or generator - there is no third choice - so to switch to PV the grid/generator combination should be taken out of the circuit configuration to avoid backfeeding one or the other. Or am I missing something?)

Docgmt said...

The larger the system gets the more expensive the parts become. Have you considered putting in isolated feeds to your house? Have one set of panels/batteries run electronics while the first feeds the house lighting. Then you can have two small inverters instead of one large one and replacement costs are lower.