Tell me why PV systems are not a scam

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Besoeker said:
Yes. Storage. That's why I mentioned it before. Hydro has it but not everywhere has the topology. We need storage at utility level in order to progress with renewables.
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Not necessarily storage, or at least not just storage. Demand management to cause loads which _may_ be time shifted to run when the renewable is available can also help to match consumption to supply.

In some areas, peak energy consumption is related to HVAC use, which is related to the availability of solar power.

-Jon
 
One interesting factor is that 'balance of system ' (mounting, inverters, etc) is now rather more expensive than the solar panels. This is why it now pays to mount panels not at the ideal angle for the sun; the panels themselves are cheap enough to make it reasonable to just add a few more.

I noticed a few years back that the output characteristics of solar panels match reasonably well with the load characteristics of LEDs. If you simply connect a solar panel to an approximately matched set of LEDs (LEDs in series/parallel so that the desired operating voltage and current matched the peak power point of the solar panel in normal sun conditions) then you can make a 'virtual skylight' without any sort of inverter or LED driver circuitry.

The basic setup is solar panels on a roof of a 'big box' with LEDs directly below the respective panel, with a much smaller roof penetration than a real skylight. Voltages and currents kept low enough that there isn't a short circuit fire risk nor a shock hazard. You get the benefits of 'free' light when the sun is shining, light that responds to clouds and time of day like a real skylight, but without a large roof penetration mucking with your roof leak risks or roof insulation. With the current cost of solar panels, it might even be cheaper than a real skylight.

Yes, I do have an economic interest in the above :) https://www.google.com.pg/patents/US9010959

-Jon
 
---Solar has become a bit of a get-rich-quick business. Some installers are a bit too slick.... some are honest.
My biz survives because so many are so cheesy...it is easy for me to shine :)

---Solar can pay for itself in 4 years. Sometimes 17 years. I always show the payback and the ROI.
Smaller systems have higher per panel costs. Smaller users also pay lower rates for each kwh. So it doesn't pay if you are under $50 or so a month....roughly!
High users of power pay very, very high "Tiered" rates! This is BIG. And they benefit form cheaper per panel installed costs.

Solar really pays because of punitive Tier pricing for high consumers of electricity, peak time pricing in summer afternoons, and net metering laws forced on monopolies. This is undeniably true.
Mixed feelings about these, but it is the structure and I have not lobbied for it.

I have customers who would otherwise pay the utility 36 cents / kwh. When you pay 3.5 times as much as your neighbor for each unit of power....and you use more of it also....solar PAYS big...see where the math is going?

Now. Add an electric car which is very popular....it adds 1000's of kwh to your annual usage, allowing lower per panel installation costs...and you qualify for a helluva rate deal called the "electric car rate" from the utility....so you get PAID high rates during day for solar generation and pay low rates overnite to charge the car. These folks pay off their system in 4 years. Honest. Then free power for 25 years.
(again, no argument here about right or wrong, it just is)

----Yes, we do assume a low cost of maintenance in our proposals, because there truly is none. Independent testing shows 20-30 year reliability and extremely low failure rates. I provide 10-25 year warranties from myself the installer and the mfctr. on panels and inverters.
Have replaced numerous components at no cost - labor or parts - to home-owner.

-----Yes, solar goes through a huge variation in output from 8 AM to noon. All this is factored in.

I mostly have customers that produce more than I promised.
and i guarantee production.
Most do.

----Would solar be financially viable without the 30% federal tax credit and utilities forced to pay retail rates? No, probably not.

----My customers have shifted form die hard greenies to show-me-the-money types.

----Finally, many people today believe in catastrophic man-made climate change ...........and solar is the solution to them. I will not express an opinion on this, but it is common perception in 2018. The point here is money has almost nothing to do with the consideration to buy solar in these cases. Money matters only in as much as......... can they afford it?
 
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gadfly56 said:
What kind of "helping hand" did Ford or Chrysler get? Or the early POCO's?
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The problem is that there is a market failure in the energy generation market as the costs of externalities are not reflected in the price. That could be significantly improved by putting a pollution tax on generators. As that is politically unpopular, an alternative approach is to subsidize less-polluting generators. Doing neither allows the market failure to continue and produces a lower utility for society.

Cheers, Wayne
 
Coppersmith, the installer who racks up the panels on a god awful looking and expensive rack to squeeze out an extra 10% at the absolute 100% ideal tilt......at more than 10% extra cost ..........is doing a dis-service to the home-owner.
 
Coppersmith,

I understand the skepticism. Lots of fly-by-night outfits.

When a decent solar guy places panels on a less than perfect roof surface, we always calculate the effect that
1. shade
2. pitch angle (slope)
3. orientation have.

These are exact and mathematically quantifiable factors.

Take away lesson? In general East, South and West are fine. North is almost always a no go.

Now, given that roofs nearly always have two opposing faces, one will always be E, S or W, the southern half of the compass rose. Hence why panels will just go co-planar to that preferred roof face.
Want numbers? Due W is 89% insolation vs due South, 100% perfect. Not a big deal.
If you now rack up the panels, because it isn't "perfect".......it'll make your neighbors puke:sick:, and your house creak :eek:hmy:under the huge wind sail effect you just created.
Oh and add more in cost than you ever will recoup in added energy!

EXCEPTION: North-facing roof. Rack 'em up South!

The installer who racks up the panels on a god awful looking and expensive rack to squeeze out an extra 10% at the absolute 100% ideal tilt......at more than 10% extra cost ..........is doing a dis-service to the home-owner.
 
infinity said:
......... my biggest problem with them is that they are so ugly...
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agreed. paint the conduit or hide it or minimize it. Often a beautiful array, snug to the roof, with no exposed j-boxes or exposed mounts...will be ruined by a 1/2" EMT run across the roof.
 
ggunn said:
Coal and nuke plants can't be started and stopped quickly enough to smooth out the fluctuations in energy production from solar and/or wind, but natural gas generators can.
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It's been 40 years since I worked for Duke Power (now Duke Energy) in the production department. I had involvement in coal, oil, gas, and nuclear; we had hydro, but it was a different department.

I think your understanding of the ability to change output is over optimistic.

Nuclear, UNDER NORMAL conditions, can probably change less than 10% per hour; I'd guess more likely 5%. It also cannot (I'm guessing here) operate well at less than about 60% of nominal. From a cold reactor to 100% generation is more than a day, less than a week.

Coal is better. If designed to do so, (and when I left in 1978, none of ours were), steam turbine operation at 40% was about as far down as it could go; ours were practically limited to 65% or so. Cold startup is worse than nuclear because temperatures are higher ... maybe 650F for nuclear, 1050F for modern coal/gas/oil. But they can probably go from minimum to maximum, or the reverse, in about an hour without undue stress. A gas fired boiler won't differ much.

For reasonable efficiency, a gas turbine will be part of a combined cycle system, with waste heat boiling water for a steam turbine. The lower temperatures allow cold startup of the boiler in probably an hour; the gas turbine can probably be at full load in 20 minutes. Neither of these will operate WELL below 50%.

Hydro is the great one ... 0-100% in a minute or two. But IIRC, we got maybe 4% of our needs from hydro.

I don't think anything except hydro can handle the minute-to-minute variation of renewables. By allowing slight voltage and frequency variation, and with the small amounts presently talked about, fossil can do pretty well. But if solar approaches 20% of the system, even handling the 10AM to 5PM smoothly varying output won't be easy. A cloudy day, from the utility standpoint, is much easier.

As our Brit said, we've got to come up with some effective storage, probably (my guess) in the 10% of daily energy load, to handle 25% or more renewable generation.

I don't think batteries are YET worth considering, but AFAIK there isn't anything except them and pumped storage. Of course, perhaps the load can be leveled; businesses, schools, industries operating more hours of the day, especially in summer when the nights are relatively cool.

It's interesting that Duke's pumped storage systems were originally intended to allow the nuclear units to operate at substantially base load.

This is just my view, and I hope some CURRENT experts can shoot my pessimism (realism?) down.
 
GeorgeB said:
As our Brit said, we've got to come up with some effective storage, probably (my guess) in the 10% of daily energy load, to handle 25% or more renewable generation.

I don't think batteries are YET worth considering, but AFAIK there isn't anything except them and pumped storage. Of course, perhaps the load can be leveled; businesses, schools, industries operating more hours of the day, especially in summer when the nights are relatively cool.

It's interesting that Duke's pumped storage systems were originally intended to allow the nuclear units to operate at substantially base load.

This is just my view, and I hope some CURRENT experts can shoot my pessimism (realism?) down.
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fwiw, Australia just switched on the world's biggest battery



~RJ~
 
jaggedben said:
Um... the Eisenhower interstate highway system? And a lot early POCO's were government.
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I'm sorry, something that came along about 70 years after the introduction of the automobile was a subsidy for kick-starting the industry? I think you need to review the principles of cause and effect.
 
Besoeker said:
"capable of providing electricity for as many as 30,000 homes"
For how long I wonder?
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From Jo Nova's website:

"There are 673,540 households in South Australia and the Big Battery can supply 4% of them for an hour with electricity, or all of the state for a bit over two minutes."

Worth noting is that the South Australian government refuses to reveal the all-in cost for the battery facility at Hornsdale. Forbes magazine has estimated the cost at $A200 -240 million. So, the "generating" capacity of 100 MW is about $US2 per watt. A combined cycle gas plant would run you about 90 cents per watt. And as long as it has gas, it doesn't run out in an hour.
 
jaggedben said:
Powerpack energy to power ratio is about 4 hours.
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Tesla is claiming they can pull at a rate of 100 MW with a total capacity of 129 MW-hrs. Kudos if they have the technology to keep from frying the batteries in a month at that draw down rate.
 
wwhitney said:
The problem is that there is a market failure in the energy generation market as the costs of externalities are not reflected in the price. That could be significantly improved by putting a pollution tax on generators. As that is politically unpopular, an alternative approach is to subsidize less-polluting generators. Doing neither allows the market failure to continue and produces a lower utility for society.

Cheers, Wayne
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"Externalities" is social mumbo-jumbo and hand waving where folks get together and fabricate a cost model that "proves" renewables are a better bet. There is not a scintilla of evidence that with modern pollution controls that there are any "externalities" left to deal with. We now return you to the real world.
 
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