Connect with us

Hi, what are you looking for?

CleanTechnica

Clean Power

Solar PV Standards — Differences Between US & The Rest Of The World

Originally published on ABB Conversations.
By Marzio Zambetti

The difference between solar PV on one side of the Atlantic versus the other

Most of us are probably familiar with differences between American electrical standards and those used in most of the rest of the world through personal electronics. Today’s laptop computers and phone chargers can accept either 110v or 220v so all you need to travel between regions is an adaptor for the plug. But it was not always so, and many electronic devices designed for 110v came to an early death when their owners plugged them into a 220v outlet on their European holiday.

In the world of solar power, there are similar standards that dictate the maximum voltage a photovoltaic (PV) panel can use. Like their consumer-level counterparts, these standards vary between regions.

Outside of North America, IEC standards (specifically IEC 60364-7-712) provide requirements for solar installations. In the US, the National Electric Code (NEC) governs public and private wiring installations (article 960, if you’re interested) while the National Electrical Safety Codes cover power generation, also applicable to solar PV.

It gets even more complicated because NEC standards also specifically require the use of equipment that is compliant with product standards established by Underwriters Laboratories (UL).

So, what’s the difference between solar PV on one side of the Atlantic versus the other?

In a word, it comes down to voltage. US standards cap the operating voltage of a PV panel at 1000v but conventional wiring practices typically mean the voltage is set even lower, at 600v. Meanwhile, IEC systems typically operate at 1000v or even 1500v.

This has some important implications when it comes to overall system efficiency and cost. Higher system voltage allows for:

  • A reduced of number of source circuits and a reduced numbers of conductors for a system of the same capacity
  • A reduced number of overcurrent protection devices, inverters, disconnectors and a subsequent reduction in labor cost
  • Smaller cross-section conductors (i.e., lower materials cost)
  • Reduction of wire resistive losses
  • Increased efficiency at the inverter stage
  • Increased power at the same current rate

These benefits have not gone unnoticed by the US standards bodies, and are at the center of the debate now taking place in anticipation of a revision to the NEC this year. If the codes are changed to allow higher voltage levels, we could see a drop in overall PV system costs once equipment vendors adapt to the new standard. It’s hard to say how much of a reduction the end user will see, but even a small improvement would certainly be welcome.

 

Advertisement
 
Appreciate CleanTechnica’s originality? Consider becoming a CleanTechnica Member, Supporter, Technician, or Ambassador — or a patron on Patreon.
 
Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.

Written By

We publish a number of guest posts from experts in a large variety of fields. This is our contributor account for those special people, organizations, agencies, and companies.

Comments

You May Also Like

Clean Power

Killer combo of offshore wind and green hydrogen indicates that rapid decarbonization is achievable, if policy makers do the right thing.

Clean Power

Green hydrogen is going down in cost, and concentrating solar power could pick up the pace by ditching electrolysis in favor of a thermochemical...

Clean Transport

While the US Postal Service fiddles with gasmobiles, Ford Motor Company launches new E-Transit electric vehicles at the delivery van market.

Clean Transport

In its quest to decarbonize and electrify, the US Air Force is upgrading its MHU-83 Jammer munitions lift truck.

Copyright © 2021 CleanTechnica. The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by and do not necessarily represent the views of CleanTechnica, its owners, sponsors, affiliates, or subsidiaries.