Energy to build a PV cell?

There is, of course, no point whatsoever in using conventional silicon pv solar cells.

Conventional silicon pv never was, is not now, and never will be capable of ever becoming a renewabls and sustainable energy source.

Not one net watthour of silicon pv solar electrical energy has ever been generated.

New technology involving CIGS may eventually get us as much as one third of the way towards renewability and sustainability.

See

Hi Don,

I take it you're aware that Wikipedia disagrees with you insofar as whether or not PV cells generate any net energy? -->

Wikipedia is, of course, not even wrong.

Yes, a silicon cell may be able to return as much as five times its manufacturing energy at its terminals. This is not remotely enough for NET energy breakeven.

The net energy analysis has to be done on the SYSTEM level, not the panel level.

Use of an equivalence of one dime = one kilowatthour (as contractually agreed to with your utility) greatly simplifies understanding why conventional silicon pv never will be able to become renewable or sustainable.

The amortization cost today of the synchronous inverter alone consumes far more than 100 percent of the panel net energy.

Even if the cells were totally free.

See

See

That link doesn't work (the other one was OK).

Oops. should be -A

I grabbed a copy of the analysis they cite:

Maybe my eyes are getting old, but I didn't see where they give a cost per kW for the cells themselves, the system cost, maintenence costs or anything. (I just did a search for '$').

Until you redo that calculation at a future power price of about $.50/KWH ... $.10 is already ancient history in most places, .50 and higher is on the way.

For an 8 kW system at $45k installed, financing cost is about $300/month and your avoided cost for a net metering hookup (you wouldn't consider it if net metering wasn't available in your area) is about 8 kW * 5 hours/day * 30 day/month * $.15 /KWH = $180/month saved on your electricity bill right now if you live in sunny southern California for example.

In another decade power prices will probably double and net metered solar probably will pay back in some areas even if you don't use it to avoid the cost of a diesel generator backup power system.

Only true because you are comparing to the watthours you could buy with the same money at todays prices, not true of actual electrical watthours produced vs consumed in mfgr of the complete solar power system.

Copper Indium Galliun Selenide solar cells may eventually replace silicon solar cells, or mabey it will work out to be some other solar cell technology, but they are still solar cells in my book, not yet to be counted out as potentially useful.

And there are places where conventional silicon solar makes sense right now, like my tree farm where I avoided the cost of 4 miles of utility poles and wire required for a grid connection by using a 100 watt panel and a battery :-).

Nice info, but I think zone refining is ancient history today and most purfication is done on gasseous SiH4 which is made from the SiCl4 which you have described the production of. Certainly all epitaxial deposition is done from SiH4 which has been purified with molecular sieves and the like.

Net metering is a subsidy and a hideous tax on other users. Simply stealing electricity from your neighbor makes more economic sense.

Further, a typical domestic synchronous inverter when fully and properly amortized today requires more than 100 percent of the electricity sent through it to pay for itself.

Proof of all this is very simple: Not one power utility anyplace anywhere is routinely using conventional silicon pv for cost competitive electrical generation.

The reason is that conventional silicon pv never was, is not now, and never will be renewable or sustainable. The latest of CIGS technology MAY get us as much as one third of the way towards renewability and sustainability.

And those utilities with solar array research facilities will not tell you their avoided cost equivalence because it is ludicrously noncompetitive.

Note that when a pv panel matches the utility avoided cost, you have gained ABSOLUTELY NOTHING. All you have is an elaborate smoke and mirrors "paint it green" use of conventional power sources.

Only when pv panels can provide energy at substantially under current utility rates does sustainability emerge. And only on THAT FRACTION that is below and displaces conventional sources.

The more conventional silicon pv panels that are installed, the FURTHER in the future any possible renewability or sustainability will occur.

A reasonable estimate of the California energy subsidy is that it will SET BACK pv renewability and sustainability by at least FIFTY YEARS.

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See

Wonder why it is that gasoline and electricity prices are highest in California?

Fortunately most of us haven't been Californicated ;-)

I paid 9.2¢/KWH this past month (including excessive taxation).

Unfortunately it was for 6821 KWH :-(

...Jim Thompson

You say that it is their....*poop* ??

Yep ;-)

...Jim Thompson

I think I read somewhere that they pass direct current axially from one end of the rod to the other end so that the current passes from the solid rod through the liquid section and then back into the other solid section of the rod. Because of the difference between the solid and liquid silicon, the Peltier effect causes the solid-to-liquid boundary at one side of the molten zone to be heated and the other boundary to be cooled, thus moving the molten section along the rod.

Chris

RF heating.

They move the "zone" from one end to the other, "sweeping" the impurities to one end, where they are sawed off.

I haven't heard of that one, though I'm certainly no expert anymore on silicon refining.

...Jim Thompson

Not always. In some cases, the net metered rate (essentially the same as the residential rate) is lower than the utilities avoided cost. If this is true, paying the net rate makes a lot of sense for a utility.

Which is all the more reason that utilities should be grinning from ear to ear whenever some moron invests in such a system and then only accepts net rates in return.

Many utilities have high capital costs, particularly in places that have hydro power (essentially zero fuel cost) or thermal plants used for peaking (gotta keep paying the bond whether the turbines are spinning or not). The ability to get a private producer to pick up the investment risk in return for a payment per delivered kWh is worth quite a bit to a utility.

If the utility power mix includes both high priced peaking thermal sources (gas turbines, for example) plus cheaper base load (hydro or coal), the spot market price can be many times the net metering rate. Enron figured this one out in California.

They will tell the state utilities commission, if they expect to include its cost in their rate base.

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Not that i would call myself an expert, more of a casual historian really, (molten) zone refining was primarily used on Germanium {GE Transistor Manual, 7th edition}. Silicon refining has primarily been done with liquid / vapor phase change on Silane SiH(4) and or Silicon tetrachloride SiCl(4). Typical semiconductor industry Silicon purities are better than

My last bill was 4.9 cents/KWH & 4.979 cents/KWH fuel charge (9.879 cents/KWH) for 883 KWH.