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The Right Inverter (New Law Compliance)

October 18, 2019

Making the decision to save money, be more energy independent, and help the environment by installing solar panels may have been easy, but wading through all of the regulations governing solar energy production and use in California is a different story. That requires experience and well honed expertise. It also requires keeping up with the times - with the constant stream of new laws appearing on the books.

One such new regulation that has a big impact on solar system design and installation in California is the "Rule 21 Mandate" governing which inverter types are permitted on new solar systems. To get the most efficiency out of your system, avoid overloading the grid, and to keep compliant with all regulations - rely on Sun Solar Electric to handle all of your solar panel and system needs!

For a free consultation with a Sun Solar Electric representative, call us today at 707-658-2157. We are located in Sonoma, CA, and serve all the surrounding counties of the SF Bay Area.

About Rule 21

The Rule 21 Mandate went into effect in California on 8 September, 2017, and it is already having a major impact on the energy industry. Rule 21 sets up certain requirements for utility-home owner interconnection agreements. Specifically, it applies to PG&E, SCE, SDG&E, investor-owned utility companies, and utilities governed by the state Public Utilities Commission. Other, municipal, utility providers are also likely to follow Rule 21 stipulations even though technically not yet required to do so. And as other US states often "copycat" California when it comes to solar issues - Rule 21 could ultimately have a nationwide impact.

Rule 21 is all about increasing the capacity for solar and other renewable energy sources being harnessed into the state electric grid in a safe and efficient manner. Already, our state is on track to hit 12,000 megawatts of solar power produced annually from residential sources by the year 2020.

The problem is that as solar input into the grid becomes more voluminous, inverters need to be more reliable and able to handle large two-way power flows with ease. Originally, solar inverters were supposed to auto-shut off at the slightest sign of grid turbulence, but with so much solar energy on the grid today, the answer must be to switch to more powerful inverters. Otherwise, the sudden shut-off of numerous solar inverters all at once could actually increase the volatility level of the grid.

Three-Phase Implementation

Rule 21 already began to be implemented in September of 2017. Phase One raised the bar for voltage/frequency handling abilities of solar systems so they can handle greater "flux" in the grid.

Phase Two will set up a "common computer language" that will enable solar inverters, the rest of solar systems, and utility systems to better communicate.

Phase 3 is going to address adding yet more inverter functions, such as maximum-power control, remotely connecting or disconnecting, and data monitoring.

Phases 2 and 3 do not yet have a fully spelled out timeline for implementation. But it's clear that they are coming and coming soon. So, you want an inverter that will not only comply with current regulations but also with those about to be implemented. No one wants their inverter out of date or worse (have to replace it) within a year or two after installing it!

We Keep You Compliant with Rule 21!

Talk to us about all aspects of your solar system - including about your new inverter and keeping it Rule 21 compliant. We are deeply experienced in this area and can help you make an informed decision you will not regret.

There are seemingly unending multitudes of inverters on the market today. The average person has no hope of wading through all of the technical details and specs about each one and finding the best choice. But we are professional solar system installers who are fully familiar with the top brands, types, and models of solar inverters. And we know which ones are up to Rule 21 standards - and which ones exceed those standards.

Some inverters and microinverters come with explicit Rule 21 certification and letters of compliance. They also may come with software systems specifically tailored for full compliance and ease of use. Such software can usually be updated later on if necessary as well.

Our staff knows how to select the grid profile appropriate to your solar system and solar production location, in accord with the site activation form. We also know how to determine if you need a new inverter or can simply make updates to your existing inverter. Furthermore, we can ensure your system is capable of generating a legitimate compliance report immediately upon request.

Smarter Inverters for A More Stable Power Grid

The more toward "smart" inverters didn't actually begin in California, but it was first pursued energetically by Germany. German companies were already using advanced solar inverters to stabilize their power grid, and California is taking the lead in introducing the concept to the United States.

In Germany, Japan, California, and elsewhere where solar power is on the rise, the move to smart inverters is a big change. Only 1% or so of California's power consumption is of solar energy produced on roof tops of homeowners scattered throughout the state - but smart inveter technology means that solar systems will double as grid regulators as well - including at night when they're not producing energy. 

Such inverters can regulate voltage level and support the grid in a variety of other ways. Your inverter is the link between you "private energy plant on your roof" and the big pool of power flowing out there through the power lines. Inverters are responsible for converting DC current produced by rooftop photovoltaic cells into grid-ready AC current. Inverters can also produce "reactive power," which is basically AC voltage that is ahead of or behind the general grid voltage - and this reactive power is used to control the voltage of the line as necessary. By adding reactive power, the line voltage is upped, while reducing it also reduces line voltage.

Smarter inverters is good news for homeowners and power suppliers alike. Why? Because utility companies have long seen solar inverters as an unfortunate nuisance, as they would trip off at the slightest sign of grid instability - to protect power line workers from unexpected and dangerous grid surges. But now, all that is beginning to change.

Germany's Example

The more widely distributed your power generation sources (which skyrockets with everyone having their own solar panels), the more difficult it is to maintain proper power quality on the line. Germany is the perfect example of this phenomenon: in the past, when power usage dipped low on the grid but solar input was still high, it would cause high voltage levels. This led to cessation of installing new solar panels connected to grids already being affected in this way. Then, smarter inverters were introduced that solved the problem.

The smart inverters now subtract excess reactive power whenever their solar panels are at 50% or higher solar energy output into the grid. This, in turn, allows a greater number of rooftop solar systems to share the same line and grid. In fact, 40% more PV solar panels can be on the same line now as compared to without smart inverters. 

The other way to correct the problem would have been to upgrade all the distribution feeder lines with thicker cables - but that would have been much more expensive than simply replacing "dumb" inverters with "smart" ones.

Additionally, Germany has mandated that inverters must be quicker to react to grid emergencies. Whenever excessive supply to the grid makes AC current jump over the Europe-wide 50 hertz standard (even to only 50.2 hertz), inverters have to cut down solar system output rather than simply shut off. Although such hertz variations are rare in Europe, Germany was worried of the possible tsunami-like effects of a sudden, massive shut down of solar inverters all at once all across the country.

California's Story

The experience of Germany was a warning light and an instructive and constructive example to California and much of the rest of the world. As early as 2013, California began to work towards pushing for the smartest possible inverters on its statewide power grids. So far, there hasn't been much of any problem due to too much solar on the grid, but as solar panels become more and more popular in-state, the potential for a a problem increases. Thus, Rule 21 is a proactive rule meant to avert certain dangers and to harness certain "bonus benefits" to boot.

California is beginning with the standards for inverters active now in Germany, and is working towards increasing those standards yet further. The same benefits as smart inverters had in Germany will accrue here - and California is set to become the world leader in smart inverter innovations. For example, California is looking to use inverters that detect the percentage of excessive voltage and then respond in proportion, absorbing just enough reactive power to drop the voltage back to normal. If there is too little voltage, likewise, more reactive power will be released to bump up the voltage to the normal level. This means that each solar system will act more like a miniature power station, with equipment that mimics the FACTS technology of power substations.

Some regulations for solar inverters in California went into effect in 2016, and the first step of Rule 21 did so in 2017. New stages will likely follow in 2019 or beyond. Manufacturers have had plenty of advance notice on these changes, and so finding a compliant inverter will become less and less of an issue as the years roll on. And the cost is likely to come down too as the supply catches up with the demand.

Looking to the future, California is aiming for "coordinated real time inverter control" across the state. This is why Step Two of Rule 21 involves communication link upgrades, which will enable such coordination. Realistically, it could take up to 5 years for step two and three of Rule 21 to become a reality, and chances are, new inverter or other solar equipment standards will continue to rise thereafter as state officials continually seek to improve grid stability.

Why Choose Sun Solar Electric?

Sun Solar Electric has developed a strong reputation in Sonoma, CA, and beyond through good old fashioned customer-first service and solid expertise. We always keep ourselves on the cutting edge of the solar industry to the benefit of our many clients.

We can handle every aspect of installing your new solar system from beginning to end. And if you need to upgrade your inverter or another component, we can take care of that for you too!

Our high customer satisfaction rate, consistently positive customer reviews on Yelp and elsewhere online, and the many new clients we get on referral from past ones testify to our success.

We encourage you to own your own solar system instead of just "rent" it, and we help you enroll in programs that will make that goal attainable. We also are intimately knowledgeable of federal, state, and local tax benefits and rebates connected with solar system installations - and we know how to help you get the biggest possible output for the lowest possible price.

Looking for Solar Panel Experts Near Me? Contact Sun Solar Electric Today!

We at Sun Solar Electric are always 100% up to date on all new state and federal regulations affecting solar panel installation. That includes Rule 21 and its effects upon inverter selection. Don't risk choosing a less than effective or less than compliant inverter - talk to us by calling our solar electric company at 707-658-2157 today for assistance!

We have long served our home town of Sonoma, CA, and all the surrounding counties of the SF Bay Area with comprehensive and top-tier solar system installation and servicing - and we can do the same for you!

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