Solar Electricity Quality

RoadTripper · « **on:** 25 Jun 2016, 03:20 pm »

Does having/using solar panel/power obviate the need for power conditioning? If so, why. If not, why not? Thanks in advance.

ctviggen · « **Reply #1 on:** 25 Jun 2016, 03:24 pm »

You mean in a house that's off the grid? I have solar, but we're on the grid (we sell our extra power during the day -- if there is any -- to the electric company and draw from the grid at night). So, you'd still "need" power conditioning.

macrojack · « **Reply #2 on:** 25 Jun 2016, 04:02 pm »

Not sure what you are asking but if you set up a DC system using solar panels to drive your system independent of the rest of your house circuitry, you will have cleaner power than the best conditioned AC. On the other hand, I believe Vinnie Rossi's LIO system eliminates the need for power conditioning also by using a capacitor bank to cleanse. Better read up on that though. I'm sure I did not represent the design accurately.

RoadTripper · « **Reply #3 on:** 25 Jun 2016, 04:06 pm »

ctviggen:: Thanks, that's exactly what I was getting at. You did point out something that I had overlooked. At night you're getting your power from the electric company. How about during the day? Better yet, how about when you're in the boonies and there is no "grid"?

macrojack:: That sounds like a cool idea, to have a dedicated bank of solar panels that don't go through their normal inverter. Which then goes on to a dedicated DC circuitry which then drive your what??? exactly? Doesn't the 'what' have to be designed as battery powered in the first place for this idea to work?

srb · « **Reply #4 on:** 25 Jun 2016, 04:17 pm »

A solar panel generates DC and that needs to be converted to AC by an inverter to run standard household AC items. The quality of the inverter will determine the quality of the AC. It should be a "true sine wave" inverter, but even then the sine wave quality varies between inverters.

However, if the system is isolated from the grid it should not have any additional noise or artifacts that might normally be generated outside the home, but would still be susceptible to noise generated by other devices and appliances in the home.

To run audio components directly off of solar powered battery storage would require that the component have an external DC power supply jack of the same voltage as the battery bank (12V, 24V etc.) or some type of intermediary DC regulator would be needed to adjust the DC voltage to the component.

Steve

ctviggen · « **Reply #5 on:** 25 Jun 2016, 05:31 pm »

Quote from: Seminarian on 25 Jun 2016, 04:06 pm

ctviggen:: Thanks, that's exactly what I was getting at. You did point out something that I had overlooked. At night you're getting your power from the electric company. How about during the day? Better yet, how about when you're in the boonies and there is no "grid"?

During the day, it depends. If it's sunny and not much is running, you will use all the power you generate. Last month, because we started our pool and had a hard time getting it to clear (had to put in a new filter), we had the pool pump running full blast 24/7. Even though we generated a lot of power (1,641 kWhrs), we used more than we generated. And we went on vacation, too, which means we're not using lights (although I do have lights that go on and off per a program).

RoadTripper · « **Reply #6 on:** 25 Jun 2016, 05:40 pm »

ctviggen:: Did you mean "Unless it's sunny and not much is running"?

ctviggen · « **Reply #7 on:** 25 Jun 2016, 05:43 pm »

Quote from: Seminarian on 25 Jun 2016, 05:40 pm

ctviggen:: Did you mean "Unless it's sunny and not much is running"?

Yes, thank you. I've been tracking our data for a few years, and we usually make more electricity in the summer, but use more in the winter. We have an in-law apartment that gets its heat from heat pumps.

Folsom · « **Reply #8 on:** 25 Jun 2016, 05:48 pm »

I would use power conditioning. But then again I don't think there's a good substitute for AC's gusto.

Check pretty well that the equipment can pay for itself. For various reasons this has been true and not true state to state.

Phil A · « **Reply #9 on:** 25 Jun 2016, 05:59 pm »

Have solar but off the grid but do use a conditioner

mikeeastman · « **Reply #10 on:** 25 Jun 2016, 06:50 pm »

Live off the grid and power my amps from a dedicated line straight off my inverter. I have no idea how good my power is but my amps sound good to me. I thought about trying some conditioners , but I know my power isn't going to need the same conditioning as on the grid power so I'm not sure what to try.

Phil: what inverter do you have and what do you use for conditioning?

Folsom · « **Reply #11 on:** 25 Jun 2016, 06:51 pm »

Quote from: mikeeastman on 25 Jun 2016, 06:50 pm

Live off the grid and power my amps from a dedicated line straight off my inverter. I have no idea how good my power is but my amps sound good to me. I thought about trying some conditioners , but I know my power isn't going to need the same conditioning as on the grid power so I'm not sure what to try.

macrojack · « **Reply #12 on:** 25 Jun 2016, 08:20 pm »

When you are connected to the grid your production goes into the grid. You are not using your production during the day and the power company's at night. It all comes from the same pool day or night. That's why I have 2 meters - one shows production and the other shows consumption. There is no other separation.

I'm not a scientist, nor do I have much knowledge of how electricity works but I have been told in the past that DC provides a quieter and stiffer current. Are either of those claims true?

mikeeastman · « **Reply #13 on:** 25 Jun 2016, 08:46 pm »

The DC may be quieter but the question is not is the DC quieter but is the AC made by the inverter better. Even if the DC is better you are not taking the DC straight to your equipment but into batteries and then the DC is pulled from them. I know that some of the charge controller used is solar can pick up RF and send it into the system, not a problem for me as I live in the boonies.

Wayner · « **Reply #14 on:** 25 Jun 2016, 08:48 pm »

In the very early days of electricity and the industrial revolution, it was discovered that DC voltage suffered severely when traveling over any real distances. The formula is when voltage drops, so does the current.

Tesla, thru his genius/insanity, discovered that if the electricity (voltage) was given some movement (hence the sine wave), that voltage drop could be drastically reduced, thus saving the precious amperage, over long distances. How he ever came to this correct conclusion, I will never understand, but he did and his theories worked.

Of course nowdays, we have 3 phase "industrial" power, which has 3 separate electrical circuits, 120° apart (as in sine wave) to power great big industrial motors (amp driven).

I actually have an ammeter that will go up to 150 amps, D.C. and the model I have is older then the one in the Smithsonian Museum (I have seen it), both made by the same company (Dungan Instrument Co, Albany NY).

'ner

Folsom · « **Reply #15 on:** 25 Jun 2016, 09:01 pm »

Wayner, the answer is simple. You can use transformers with AC, but not DC. He knew higher voltage travels farther over any resistance, to the point of arcing in the air. So you simply move electricity to one place or another at very high voltage, and use a transformer to adjust it once it arrives.

Obviously the drawback is you need tons of transformers, including in our appliances.

HAL · « **Reply #16 on:** 25 Jun 2016, 09:15 pm »

The best 2KVA true sinewave inverter I found awhile back had a THD spec of 2% at any output useful. That was about the same as I measured with my Fluke 43B line analyzer in the house. This was running off of 4 paralleled 12v AGM 100Ah batteries fully charged.

As long as it is offline it will be less noise and transients, but the same distortion level. Higher than 2% you start having problems with DC on the AC line from what I see. Then some transformers start getting saturated with DC and start mechanically humming.

You could run the true sinewave inverter into something like a PS Audio Power Plant for lower THD sinewave output, but take a loss in efficiency.

This assumes a battery power system being charged by the solar panels for night time running after daylight charging. Possibly something like the new Tesla battery pack for home use.

Russell Dawkins · « **Reply #17 on:** 25 Jun 2016, 11:21 pm »

Quote from: Wayner on 25 Jun 2016, 08:48 pm

In the very early days of electricity and the industrial revolution, it was discovered that DC voltage suffered severely when traveling over any real distances. The formula is when voltage drops, so does the current.
'ner

I used to think this, too, but to my surprise discovered that DC transmission is much more efficient in terms of losses en route and cost of transmission towers and equipment—so much so that it can offset the extra cost of AC/DC and DC/AC conversion at each end. It is the system of choice for very long distance transmission because of this. It also vastly simplifies the connection between different grid systems as must occur to share loads (the AC can be synchronized easily to the local grid during the DC/AC conversion process. Imagine the process of trying to synchronize the AC of all the systems connected in a continent-wide grid system. (I don't want to think about it).
Here's a great encapsulation of some of the considerations:
https://en.wikipedia.org/wiki/Electric_power_transmission#High-voltage_direct_current

mikeeastman · « **Reply #18 on:** 26 Jun 2016, 12:38 am »

Hal: What brand was 2kv inverter? Did you run any test on the lager inverter?

HAL · « **Reply #19 on:** 26 Jun 2016, 01:19 am »

It is a Xantrex inverter. Only one I could find at the time. Never tried a larger one.