Solar production. Panel ratings/claim vs reality

[sd455dan]

Guess I will get into the solar thing as well. As much for backup power as reducing grid use, so going with Hybrid inverter/ batteries and bifacial panels.


Rechecked my bills and I misquoted our rates in the ev thread, base rate of 8.23 cents KWH for the first 1250 KWH and .1028 above that. Our electric power co-op will buy back over production at 4 cents a KWH.

 

[fatjay]

Guess I will get into the solar thing as well. As much for backup power as reducing grid use, so going with Hybrid inverter/ batteries and bifacial panels.


Rechecked my bills and I misquoted our rates in the ev thread, base rate of 8.23 cents KWH for the first 1250 KWH and .1028 above that. Our electric power co-op will buy back over production at 4 cents a KWH.

Make sure you are adding generation and transmission for your overall cost.

Also be weary of that, they'll buy back, but I've heard of companies starting to charge transmission on the buyback. Since you're using their lines.

 

[sd455dan]

Make sure you are adding generation and transmission for your overall cost.

Also be weary of that, they'll buy back, but I've heard of companies starting to charge transmission on the buyback. Since you're using their lines.

If they don't buy back or I use everything produced, totally OK with that. Our local co op has been great over the years. Not many grid down days and they have always fixed things real quick.

Now looking into methods of ground mounting panels with angle adjustment for different times of year. The prebuilt mounting system/ kits seem to get pricey quickly. Not into roof mounting with the amount of snow we can get in some winters. Seems being able to set panels almost vertical on a ground mount would also help with sluffing the snow off versus a low angle roof trying to pull it off with a roof rake, and work well with snow reflection feeding the backside of the Bifacials.

Just thinking out loud, reading this thread with interest.

 

[paulsharvey]

Make sure you are adding generation and transmission for your overall cost.

Also be weary of that, they'll buy back, but I've heard of companies starting to charge transmission on the buyback. Since you're using their lines.

The power company has significant cost in the design, construction, and maintenance of the infrastructure. If they paid you they charge customer distribution rates; every watt hour You generated would cost them probably 25% more than they can pass down the line.

 

[ultrarunner]

If they don't buy back or I use everything produced, totally OK with that. Our local co op has been great over the years. Not many grid down days and they have always fixed things real quick.

Now looking into methods of ground mounting panels with angle adjustment for different times of year. The prebuilt mounting system/ kits seem to get pricey quickly. Not into roof mounting with the amount of snow we can get in some winters. Seems being able to set panels almost vertical on a ground mount would also help with sluffing the snow off versus a low angle roof trying to pull it off with a roof rake.

Just thinking out loud, reading this thread with interest.

I only adjust angle of my panels twice a year…

 

[Grumpycat]

Seems being able to set panels almost vertical on a ground mount would also help with sluffing the snow off versus a low angle roof trying to pull it off with a roof rake.

The latest thing is the bifacial PV panel which is partially sensitive on the backside. Can sometimes make power from that which is reflected from the ground.

Have been some interesting experiments in mounting these panels vertical. Good yield early and late in the day. Area under the curve of production is similar but not quite as good as "optimal angle" mounting. Depends on your latitude.

 

[Grumpycat]

The power company has significant cost in the design, construction, and maintenance of the infrastructure. If they paid you they charge customer distribution rates; every watt hour You generated would cost them probably 25% more than they can pass down the line.

Probably worse than that. The Federal Grid Tie law says the utility only has to pay the Audited Incremental Cost of Generation. They don't have to pay more than it would cost to produce a kWh themselves. For TVA that is about 2.5¢/kWh. Most TVA associated utilities charge around 10¢/kWh for the power delivered to one's home. The difference is the cost of that distribution grid.

Long ago I wise experienced engineer told me, "The biggest cost in running an electric power utility is the cost of money." In other words, "interest".

 

[ultrarunner]

Probably worse than that. The Federal Grid Tie law says the utility only has to pay the Audited Incremental Cost of Generation. They don't have to pay more than it would cost to produce a kWh themselves. For TVA that is about 2.5¢/kWh. Most TVA associated utilities charge around 10¢/kWh for the power delivered to one's home. The difference is the cost of that distribution grid.

Long ago I wise experienced engineer told me, "The biggest cost in running an electric power utility is the cost of money." In other words, "interest".

For decades PGE always cited the high cost of generation as basis to raise rates… building, operating, fueling, etc.

Then home solar comes along and about face… the cost of generation is incredibly low but now it’s distribution that is so expensive.

All I know is the little guy always pays in the end…


Now they want to means test customers across the board so higher income residences will pay more…

 

[ponytug]

Guess I will get into the solar thing as well. As much for backup power as reducing grid use, so going with Hybrid inverter/ batteries and bifacial panels.


Rechecked my bills and I misquoted our rates in the ev thread, base rate of 8.23 cents KWH for the first 1250 KWH and .1028 above that. Our electric power co-op will buy back over production at 4 cents a KWH.

If you want solar for backup, I would make sure that you design that in. Some inverters and microinverters are grid forming and can function during outages, but most can't. For starting larger loads, having battery storage helps, and is necessary for overnight uses.

My $0.02 is plan a system that includes batteries that can be recharged from the generator for those winter blizzards, and summer fires that shutdown solar production.

All the best,

Peter

 

[sd455dan]

The latest thing is the bifacial PV panel which is partially sensitive on the backside. Can sometimes make power from that which is reflected from the ground.

Have been some interesting experiments in mounting these panels vertical. Good yield early and late in the day. Area under the curve of production is similar but not quite as good as "optimal angle" mounting. Depends on your latitude.

Have you decided on a system, Last post think I saw you were considering Tesla power walls or EG4 ?

If you want solar for backup, I would make sure that you design that in. Some inverters and microinverters are grid forming and can function during outages, but most can't. For starting larger loads, having battery storage helps, and is necessary for overnight uses.
My $0.02 is plan a system that includes batteries that can be recharged from the generator for those winter blizzards, and summer fires that shutdown solar production.

All the best,

Peter

Right or Wrong, I pulled the trigger on a 'DIY' EG4 kit, 12KW output hybrid inverter, 18k PV input, 28.6 KWH battery power, Panels , 450 watt (540 watt max) 41" x 7' and heavy @68lb. but they did do Very well in the Ice ball impact testing and are a Tier 1 manufacturer.

PV DC into the Inverter

Inverter has pass through for a full 200 amp grid service which I do need It can also be paralleled with more 18kpv's if wanted. Rated PV is 14.4KW (32 bifacial panels) but probably be lucky to get 1/2 of that in output up here I would guess.