Solar panel related question -- help please

Not sure what it stands for but these are the primo batteries for off grid... Expensive though.

I'm sure there are some environmental impacts but yes, the lead is

And, I errored in my decimal point on the $0.01 per kW-Hour... We have lots of hydro here in the PNW. Very cheap power.

The power rarely goes down in my neighborhood but it sure does not too far from here.

boB

Prices for energy are going up but 10 cents per kW-Hours is what I meant. At least in the summer time. Probably not for long though.

boB

HuP® (High Utilization Positive)

That's not quite what I meant. Most PV systems include some kind of data logger. Usually the numbers go via the internet to the vendors data dumpster where they are then processed into human digestible tables, graphs, and projections. Only a few systems are publicly accessible. I was thinking that the owner would login to the data collector site, and supply the tables, graphs, and projections rather than just an opinion.

I've had fair luck using the drive around method. Depending on the owner, I'll either get a glowing report of substantial cost savings, or a nightmarish horror story of unscrupulous contractors, marginal hardware, evil planning departments, and inflated production estimates. One home owner had printed a prepared report denouncing everyone involved and included details of ongoing litigation. I've also blundered into surprises, such as the owner who's immovable rooftop solar array reflected enough light into the neighbors house to inspire the neighbor to seek relief in the courts. I don't have a huge amount of experience doing this, but what I have done has been educational, informative, worthwhile, and sometimes bizarre. At a minimum, I became familiar with the reputations of the local contractors.

Some online home PV systems production data: Ext.data.Store: We are sorry, but due to an internal error, we cannot fulfill your request. Please try again. If the problem persists, please contact SolarEdge support for assistance. Another day, another Javascript error.

California solar power statistics. The site is currently down for maintenance. Please check back in 15 minutes. It's been down for at least an hour. Another bad day for computers.

Who do you think pays those taxes? Businesses only collect them for the government, but the consumer pays them all.

Try to smelt the scrap 'lead' from a bad LA battery and you'll discover that it is no longer lead, but lead compounds.

I call such patents "place holders". They outline a potentially viable technology without the slightest effort to indicate how it might be accomplished. When someone actually does produce something that works, they sue claiming it was their idea. It would be nice if the patent office would return to the 19th century when it actually demanded a working model in order to obtain a patent or at least produce a working model in order to prevail in a litigatory contest.

Did that include the necessary rectifier or just the "RF" power received by the antenna? Terahertz rectifiers are not easy.

Here's one report for IR detection at about 6.5 microns. No rectification in their test or model. Just RF capture, some alleged model verification, but no test results:

Some people are claiming 90%. I guess that's what it takes to get a research grant.

I have high hopes for this technology to eventually produce a viable alternative to PV solar power. Now, you're suggesting that it's unlikely. Is it really that bad?

Recycling: In 2011, about 1.20 million tons of secondary lead was produced, an amount equivalent to 83% of reported domestic lead consumption. Nearly all of it was recovered from old (post-consumer) scrap. I wish they would clean up the English in these reports. What it's really saying is that 83% of lead produced comes from recycling. Note that China mines about half the worlds annual production of new lead.

In some countries, the metallic lead is recovered by burning the battery, which reduces the lead oxide to metallic lead. The environmental impact of such dirty operations probably has no global impact, but can certainly trash the area around the burn site.

I'll spare you my rant on stupid EPA regulations and leaching lead into drinking water.

My guess(tm) is that the batteries were made in about 1975. Still going strong. The secret is to not let them discharge very much (as well as the usual maintenance items).

Calculating "average" power costs is tricky in California. PG&E has various consumption based tiers, where heavy users pay more per kW-hr. There are also time of use adjustments, seasonal adjustments, and different rates for agricultural, commercial, residential, subsidized baseline, industrial, etc. For residential, I just look at the mid summer (worst case) bill and find the rate at which the user is paying for the bulk of their electricity. The PG&E web pile uses $0.13/kW-hr to calculate my average electrical costs, but looking at the bill from last July, I'm probably paying $0.17/kW-hr. At one of the mountain top radio sites I help maintain, the monthly bill typically runs about $2,000 with the bulk of the charges in the $0.26/kW-hr range. Note that this is the cost of the electricity, and does NOT include the cost of the service.

Well, the utility does need to get paid to maintain the grid, make repairs, add improvements, etc. Net metering policy varies by the politics of the states public utilizes commish. Here's California: The problem is that the utility companies are using transmission capacity as an excuse to put a cap on net metering. In California, if more than 5% of the "aggregate customer peak demand" comes for alternative power generation systems, PG&E will either pull their plug or refuse to pay for the power. They claim that it might someone trash the grid or cause some kind of meltdown. Never mind that in Germany about 20% of the power comes from solar and wind. It has been up to 50% during the day without any problems.

Can you please state or ask this another way ? Not quite sure what you are trying to say there. Maybe we are both talking about something completely different ?

boB

The average price of electricity varies radically by state.

It's mainly lead but evidently not too hard to separate out.

I have seen some good videos on how this is done. Might be some on U-toob.

So, in a way, LA batteries are only rented.

boB

atmosphere.

Oh. That makes a lot more sense. Thanks.

If the light would come directly from above (zenith), it would propagate through this 8 km amount of air i.e. one air mass, usually AM 1 notation would be used. about a quarter of the solar radiation is lost in the atmosphere.

Since the sun very rarely shines directly from above, a bit more realistic standard condition is used, i.e. AM 1.5, in which the light travels through 12 km sea level density air (instead of 8 km for AM1).

Hey, all he needs is a few diodes. Well, and maybe some tiny log-periodic antennas.

Yup. See

There's a lot of interest in the technology, but the hard thing about it is the huge Johnson noise of the parallel conductance. We were doing it with laser illumination for on-chip optical interconnection, so the Johnson noise of 100 ohms wasn't such a worry.

Yup. Unlike solar cells, you don't get a decent voltage out of them, so your power conversion efficiency is the pits. A visible-light photon is about 2.5 eV, so even with unit quantum efficiency, you need at least a quarter of a volt output voltage to get to 10% energy conversion.

The other thing is that an antenna interrogates a single mode of the EM field, whereas a concentrator solar cell gets about four modes per square micron. The absorbed energy is proportional to the number of modes interrogated, so you need a godawful number of antennas to get anything useful for power conversion.

You also tend to lose a factor of 2 because any one-port device only interrogates a single polarization state.

I had a project a couple of years ago to do energy scavenging in soldiers' tee shirts--if we could get a microwatt or two, we could power a transmitter in burst mode for as long as the soldier stayed, um, warmer than the environment. Efficiency at 0.1% would have been easily enough, but it didn't get funded.

Cheers

Phil Hobbs