Grid-tied solar

[dave1949]

Typical Blu-Ray disc recording patterns improve solar cell light absorption.

Blu-ray disc can be used to improve solar cell performance -- ScienceDaily

 

[dave1949]

Typical Blu-Ray disc recording patterns improve solar cell light absorption.

Blu-ray disc can be used to improve solar cell performance -- ScienceDaily

 

[dave1949]

Interesting Chinese perspective on solar energy.

I think the "... you need six square miles of our solar module to generate electricity to power an electric car." is a typo. I'm guessing six square meters.

"What is interesting with this third [energy] revolution is that it’s not about a competition for resources; it’s a competition of core technologies."

http://www.nytimes.com/2014/12/01/b...ing-group-on-the-energy-source.html?ref=earth

 

[dave1949]

The US ranks #13 for energy efficiency out the world's 16 largest economies .

http://www.aceee.org/files/pdf/summary/e1402-summary.pdf


Article on the role of energy efficiency:
http://www.nytimes.com/2014/12/01/b...&contentCollection=Environment&pgtype=article

 

[dave1949]

The November, 2014 results.

Just above the model by one-half of a sunny day, like October. Way below the two previous Novembers. We did have some gloomy weather most of the month.

Month--NREL Model (AC kWh)--2012 Actual---2013 Actual---2104 Actual

Jan.----388----------------------NA--------------440-------------360
Feb.----412----------------------NA--------------375-------------446
Mar.----509----------------------NA--------------462-------------577
Apr.----374----------------------NA--------------487-------------525
May----353----------------------NA--------------375-------------361
Jun.----308----------------------NA--------------379-------------390
Jul.-----341----------------------NA--------------377-------------395
Aug.----383----------------------461-------------470------------453
Sep.----394----------------------481-------------476------------489
Oct.----369----------------------378-------------453-------------380
Nov.----283----------------------400-------------414------------295
Dec.----331----------------------297-------------278

 

[Carl_NH]

Morning All and Dave too - thought just to post here rather than start a new thread since your advise and direction Dave led me to Revision Energy in the first place.

Well, 2 installers from Revision Energy arrived yesterday and got all the rails installed, and Solaredge inverter installed in the third garage bay area and the conduit runs in.

They installed a monitoring meter to the right of the inverter which shows total production - not really necessary, but this is their "standard practice" also I understand this can be used to track SREC but currently we don't have a purchase program in NH..

There will be no visible wiring or conduit - its all above the dropped ceiling and they came through the roof with a junction box installed with flashing under the shingles so it will be hidden by the panels. My office 16x42' is in the upstairs area - we have knee walls so all the wiring runs are inside.

Overall great attention to detail with a neat and professional installation. No, I didn't get the lowest price at $3.65 per watt but a quality installation - they hit each rafter with the 3" SST lag bolts and sealant in and around the mounting and its all level and square..

They will finish on Monday with the panel installation 24 LG300W Neon with SE Optimizers for a 7.2KW system. More pics will follow on completion.

 

[dave1949]

Thanks for the update Carl. Looking good and good to hear Revision is still doing respectable work--and glad your target date will be met. The monitoring meter is something I'm not familiar with.

Does/will your inverter keep total production history? Maybe that's something to do with the meter. Ours displays AC kWh produced since install and AC kWh for the current day's production. We didn't opt for the network interface that would allow storing hourly and daily production history. I have a feel now for how many kWhs should be produced given the amount of sunshine for the season; I walk past the inverter often during the day. That's how I monitor the system for potential problems on a daily basis, haven't had any yet.

I ended up with both In (from the grid) and Out (to the grid) meters from Central Maine Power for our net metering. I pay the monthly net difference between those two meters, or bank kWh credits if the Out exceeds the In. They are 'smart' meters with transmitters but for whatever reason the CMP truck has been coming up the drive to read them each month again lately. The meters may be 'smarter' than CMP? :laughing:

 

[Kyle_in_Tex]

Dumb question.
I know you guys are tied to the grid, so if the grid goes down in the daytime, can you run things if you disconnect at the pole?

 

[dave1949]

Dumb question.
I know you guys are tied to the grid, so if the grid goes down in the daytime, can you run things if you disconnect at the pole?

No. Not for a standard grid-tied system. They shut down when no grid power is sensed. That's for two reasons: lineman safety, and they get their 60 cycle clocking from the grid power usually since they need to sync to that to be combined with grid power in your service panel.

There are a few hybrid grid-tied systems that will run and provide limited power without the grid being up though.

 

[Carl_NH]

Does/will your inverter keep total production history? Maybe that's something to do with the meter. Ours displays AC kWh produced since install and AC kWh for the current day's production. We didn't opt for the network interface that would allow storing hourly and daily production history. I have a feel now for how many kWhs should be produced given the amount of sunshine for the season; I walk past the inverter often during the day. That's how I monitor the system for potential problems on a daily basis, haven't had any yet.

Hi Dave,

The SolarEdge Inverter along with the per panel optimizers allow me to monitor each panel output also minimize shading issues, with nearly any report hourly, daily monthly available. It will be connected to the network and as soon as we are generating power I will have a web link to view the production.

PSNH, our power co will be installing a new meter for the net metering as well once the system is operational.