Today’s solution for Rapid Shutdown requires a device to be added to every single module in a solar system – various types of Module Level Power Electronics (MLPE). This has led the industry to name this code requirement Module Level Shutdown (MLSD). This increases complexity and cost of systems, as more hardware and more labor is required. For example, in a typical residential installation with 6 kWp, the number of power electronic components needed rises from one (string inverter) to around 20 (micro-inverters or DC optimizers) - each component increases the cost for materials as well as installation time, which is another cost driver. More components also means a higher failure rate, which would cause more service cases and added workers safety hazards. 

Solar system prices in the US are much higher than in other major solar markets in the world. This higher cost is directly proportional to the high market share of expensive module level power electronics (MLPE). From 2016 to 2020, this technology reached a market share of over 90% in residential solar and 50% in commercial solar. On top of that, a duopoly controls 90% of the market for shutdown solutions, limiting customer choice and competition.

The higher costs make solar systems a less attractive investment. Cost-effectiveness is supposed to drive the adoption of Solar Energy: the more affordable solar is for customers, the quicker we will be able to transition to a renewable energy supply system.

Therefore, let's fix module level shutdown now and make solar simple, safe, and more reliable.

SOURCES:

SolarEdge and Enphase Now Control 80% of the US Residential Solar Inverter Market

Greentech Media

String inverters vs. power optimizers vs. microinverters

Energy Sage

Pros and cons of string inverters vs microinverters

SolarReviews