Grid-tied solar

[Redneck in training]

Seems to me the installers take your tax credit by overcharging. $3.50-$4.00 per kW installed in a flat roof install is normal, but is an overcharge of equipment by 30% or more than what I can buy the identical equipment myself over the net. HS

Installation of PV is easy. It is all plug in with minimal wiring. It is hard to screw it up. If the state mandates installation by by licensed installer you can get the license. Or find a licensed installer that lets you do most of the mechanical work. Iowa allows DIY so we installed the system by ourselves. The material cost was about 2.20/W and four weeks of work (mostly drilling holes and concrete work). It you mount it on a roof then you can save at least 10% of my cost. If you use string inverter you save another 10%. But I would recommend addition of optimizers. That way you will be able to monitor each panel individually and get slightly better performance especially if shading is involved. If you have tiered energy cost then turn the panels so they produce maximum power at the peak rate. In example if the peak rate is from 5 to 8 PM the panels should face somewhat west.

Since I had no clue how easy the installation would be I decided to use microinverters. Reason being when the panels are illuminated they are ON. If you use string inverter the string produces several hundred V DC and about 8-10A while single panel produces 30V and 8-10 A.

 

[Redneck in training]

My energy charge for last month was $2 plus $32 fixed charge. Total $34.

 

[Egon]

My energy charge for last month was $2 plus $32 fixed charge. Total $34.

I'll trade!

 

[dave1949]

My energy charge for last month was $2 plus $32 fixed charge. Total $34.

Mine was $22.80. $10.65 of that is the monthly minimum charge. We used our mini-split units for heat/take the chill off now and then in April. Got tired of making wood fires at the end of winter.

 

[dave1949]

Angus King proposes bill to shake up electricity pricing


Dynamic pricing coupled with more/better options for distributed generation on the grid.

 

[dave1949]

Tesla Powerwall/Powerpack sold out until mid next year. I guess I have time to figure out what such a battery system would be worth to me. I'm not sure how to go about putting an attractive target price on these things. Any ideas on how a person would figure the cost per kWh that would be low enough to become attractive? I don't know the details of how a Tesla Powerwall would integrate with my grid-tied system.

The company that installed my solar system, Revision Energy, is waiting to get their hands on a few units to see what they can do with them.

Tesla Powerwall, Powerpack sales estimate: $800 million already | BGR

Barely a week after Tesla's Powerwall battery was announced, it's sold-out to mid-2016 : TreeHugger

 

[fordmantpw]

Tesla Powerwall/Powerpack sold out until mid next year. I guess I have time to figure out what such a battery system would be worth to me. I'm not sure how to go about putting an attractive target price on these things. Any ideas on how a person would figure the cost per kWh that would be low enough to become attractive? I don't know the details of how a Tesla Powerwall would integrate with my grid-tied system.

The company that installed my solar system, Revision Energy, is waiting to get their hands on a few units to see what they can do with them.

Tesla Powerwall, Powerpack sales estimate: $800 million already | BGR

Barely a week after Tesla's Powerwall battery was announced, it's sold-out to mid-2016 : TreeHugger

Really, in a grid-tied system, I don't see how a battery like that would be much use in any situation other than emergencies where the grid is down. Basically, it would replace an emergency generator. Now, in an off-grid system, it's a different story. I think one of these systems would be awesome in an RV, though!

 

[dave1949]

Really, in a grid-tied system, I don't see how a battery like that would be much use in any situation other than emergencies where the grid is down. Basically, it would replace an emergency generator. Now, in an off-grid system, it's a different story. I think one of these systems would be awesome in an RV, though!

For grid-tied I think it depends on how the utility pricing shakes out in the future and how net metering agreements may be altered in the future. We don't have peak pricing here, so using a battery system to avoid peak rates doesn't apply.

In the most simple case, if I can charge the battery at a lower cost than grid power--and low enough to pay for the battery also--then I can keep my electric bill at the minimum charge most of the time, plus have some power without starting the generator during an outage.

A lot depends on how well all that capability is integrated in the system controls.

 

[fordmantpw]

For grid-tied I think it depends on how the utility pricing shakes out in the future and how net metering agreements may be altered in the future. We don't have peak pricing here, so using a battery system to avoid peak rates doesn't apply.

In the most simple case, if I can charge the battery at a lower cost than grid power--and low enough to pay for the battery also--then I can keep my electric bill at the minimum charge most of the time, plus have some power without starting the generator during an outage.

A lot depends on how well all that capability is integrated in the system controls.

Ahhh, I wasn't even thinking about peak pricing. We don't have that here either, but in areas where that is common, I could definitely see that. Use the battery during peak hours and grid power during off-peak. Heck, you wouldn't even need solar to save money that way. However, would you be spending nickles to save pennies? Would definitely be some interesting calculations to see how the numbers play out.

 

[KiwiBro]

Ahhh, I wasn't even thinking about peak pricing. We don't have that here either, but in areas where that is common, I could definitely see that. Use the battery during peak hours and grid power during off-peak. Heck, you wouldn't even need solar to save money that way. However, would you be spending nickles to save pennies? Would definitely be some interesting calculations to see how the numbers play out.

These batteries don't stack up financially for all but fringe-case scenarios. The equation gets even worse when trying to use them in some sort of arbitrage capacity. They are a stepping stone to getting off-grid completely and an important if not currently financially feasible one at that.

Well done to Tesla for setting a fire under the market though.