Net Metering: Phase Matching for Solar Panels

[rollingstein]

I was reading up on net metering, where the electric utility allows one to feed back excess generation by solar panels etc. onto the distribution network.

http://en.wikipedia.org/wiki/Net_metering

One question I had is, is it fairly easy to match phase for such inverters with the grid? How do they do it. These seem pretty small domestic units.

http://en.wikipedia.org/wiki/File:Feed-in_Tariff_meter_connections.jpg

 

[UltrafastPED]

They contain special circuitry to precisely match the voltage and frequency of the grid. IEEE 1547 is the standard which describes the requirements and testing: http://grouper.ieee.org/groups/scc21/dr_shared/

Here is some information on grid-tie inverters:
http://en.wikipedia.org/wiki/Solar_inverter

And a readable technical report with cost estimates for entire systems:
http://www.eecs.berkeley.edu/~phucle/EE_290N/290N_report.pdf

 

[dlgoff]

Another thing to consider about these inverter applications (i.e. grid ties) is safety. If the inverter doesn't detect the correct voltage from the utility, say during a power outage, they open the disconnect. You wouldn't want to hurt some utility worker doing work on a line they thought wasn't energized.

 

[rollingstein]

Thanks for the info.

I learned a lot of new stuff, especially the islanding bit.

The documents seem a bit light on how exactly the phase matching is done. I'm intrigued because so far I was under the impression that precise phase matching was an expensive & time consuming activity & so am surprised that a $200 box can take care of it.

 

[alphy]

I can confidently say that net metering is an important aspect of utilizing solar energy and integrating it into the existing electric grid. It allows individuals or businesses with solar panels to not only offset their own energy consumption but also contribute excess energy back to the grid, creating a more sustainable and efficient system.

In terms of phase matching, it is a crucial aspect of net metering as it ensures that the electricity generated by the solar panels is in sync with the grid's electricity. This is achieved through the use of inverters, which are responsible for converting the DC energy produced by solar panels into AC energy that can be used by the grid.

Modern inverters are designed to automatically match the phase of the grid, making the process relatively easy and efficient. They use advanced technology such as phase-locked loops and synchronization circuits to ensure that the AC output is in perfect phase with the grid. Additionally, inverters are also equipped with safety mechanisms to prevent any potential damage to the grid.

In terms of size, domestic units may seem small, but they are designed to handle the specific energy needs of a household. They are also designed to comply with safety and technical standards set by regulatory bodies.

In conclusion, net metering is a valuable tool in promoting the use of renewable energy sources like solar power. With the advancements in technology, phase matching for solar panels has become a seamless process, allowing for efficient integration into the electric grid.