This group brings together the best thinkers on energy and climate. Join us for smart, insightful posts and conversations about where the energy industry is and where it is going.

10,255 Members

Post

Something Astounding Just Happened in the Solar Energy World

commercial solar hawaii

Wow.

You probably already read the Hawaiian announcement last week about micro inverter manufacturer Enphase. It alluded to a big thing but I couldn’t quite work out what had happened so I called some friends and dug a little deeper. The reality of what these guys just did and have achieved in the real world is really quite astonishing and has big potential implications for Australia.

Hawaii has a high level of solar grid penetration at around 12%. For context, Australia is already at greater than 20% and growing and a number of areas have solar on more than 40% of roofs.

Now despite what the luddites will tell you, this is not necessarily a bad thing.  There have been plenty of studies and are plenty of cases where grid stability is being managed well even with high solar penetration. However, the reality is that such high penetration levels, solar can cause problems if networks don’t adapt, typically with voltage rise. In Hawaii, the issue was to do with varying network frequency levels.

With varying frequency levels and lots of solar, the Hawaiian network was in a lose-lose situation because (like Australia) they had set the frequency and voltage windows very tight on solar inverters to “protect” their grid. The reality is of course in high concentration or where geographic clusters of solar exist (like Australia) if the network frequency drifts out of spec then the inverters drop off-line causing spikes in demand and more voltage and frequency drift. I like to think of it as a Pyramid Style Self Induced Death Spiral.

In the case of Hawaii, that means that 140MW or so of generation could suddenly snap off then back on-line. Not ideal.

So here is where network operators have two potential decision pathways. 1) Make the rules tighter, slow down the solar uptake and try to ignore the problem away (like Australia). 2)Collaborate, innovate and take advantage of every possible technological solution you can.

In Hawaii they chose the second option and due to the fact that around 60% of the islands’ solar is Enphase equipped, calls were made. Chats were had. A new, smarterer solution was talked about.

HECO had looked at the option of manually reprogramming  inverters, but as you can imagine service call costs to 51,000 solar homes equipped with 800,000 micro inverters quickly added up to tens of millions of dollars. Uniquely, Enphase (who are heavily data focused and driven) already had the ability to remotely connect to and tweak inverter settings. Could they simultaneously, remotely and precisely make this change? And measure its effectiveness? From their headquarters in Napa Valley, California?

Yes they could.

So, the other day someone in a backroom in Enphase HQ  quietly pressed the enter button and changed the settings on 800,000 inverters across 51,000 homes. No truck rolls. No field calls. No dogs to navigate. No chatty retired engineers to talk to. One guy and a computer.

To the best of my knowledge (anyone?) a change of this importance and relevance and scale has never been done before. Ever.

Benefits? One or two.

Firstly, tens of millions of dollars of expense were avoided which will implicitly avoid that cost needing to be passed on to customers. So Enphase theoretically just helped to keep the operating cost of the networks down, and the retail price of electricity too.

Secondly, although materiality is unclear at this point, by riding through more events rather than shutting down at the whiff of a drift in frequency, 800,000 solar inverters will be on-line for more time. That delivers better yield and more savings for consumers and in the case of Hawaii, less oil burned for conventional generation. So they just made more money for their customers.

Third, Enphase’s clever little solution saved the network a whole lot of money, because they had the data, the tools and the technology handed to them on a platter by someone else, which improved the reliability of their network asset.

This is an example of simple, effective and rapid collaboration with real benefits that spread across the entire value chain. Whilst we are seeing some signs of interest down under, there is plenty of room for improvement.

We have the technology.

It is real.

It does work.

Lets just get on with it, shall we?

Photo Credit: Solar Adoption/shutterstock

Nigel Morris's picture

Thank Nigel for the Post!

Energy Central contributors share their experience and insights for the benefit of other Members (like you). Please show them your appreciation by leaving a comment, 'liking' this post, or following this Member.

Discussions

Hops Gegangen's picture
Hops Gegangen on Feb 12, 2015 11:16 am GMT

 

If one programmer at a terminal can reprogram all those inverters, could they also take down the grid by making them misbehave?

 

 

 

 

Joris van Dorp's picture
Joris van Dorp on Feb 12, 2015 12:11 pm GMT

I like the way solar penetration levels of 20% are called ‘high’ in this article. This helps dispel the myth that solar can serve most of our energy needs, which it cannot. Not by a long shot. Solar power cannot competitively deliver more than a small part of our energy needs, if any, and nuclear will have to supply most of the rest if greenhouse gas emissions are to be eliminated in time to prevent the worst effects of climate change. We should get on with enabling more nuclear power.

I am amused by the way that this article confirms that solar power does in fact cause mounting grid instability as penetration increases, a fact which is routinely ignored or denied by solar proponents. I suspect that this is comfortably confirmed now because a (partial) solution to (part of) this instability seems to have been found in Hawaii. This is amusing because it fits nicely inside the intermittent RE advocacy argumentation philosophy: “Deny problems caused by RE unless there is an easy/cheap solution, while endlessly pointing out problems with nuclear and fossil fuels, never mind whether there are easy/cheap solutions for those problems.”

Bob Meinetz's picture
Bob Meinetz on Feb 12, 2015 3:32 pm GMT

Exactly, Hops.

So, the other day someone in a backroom in Enphase HQ  quietly pressed the enter button and changed the settings on 800,000 inverters across 51,000 homes. No truck rolls. No field calls. No dogs to navigate. No chatty retired engineers to talk to. One guy and a computer.

To the best of my knowledge (anyone?) a change of this importance and relevance and scale has never been done before. Ever.

Well, the importance and relevance and scale of that achievement was probably outdone by fifteen nobodys from Saudi Arabia on 9/11, but this is solar. What could possibly go wrong?

Yikes. Forward, to the past.

Bruce McFarling's picture
Bruce McFarling on Feb 12, 2015 4:47 pm GMT

“… I like the way solar penetration levels of 20% are called ‘high’ in this article. This helps dispel the myth that solar can serve most of our energy needs, which it cannot. Not by a long shot. Solar power cannot competitively deliver more than a small part of our energy needs, if any, …”

I like the way that solar penetration of 20% is direct evidence that solar energy can provide more than “a small part” of our energy needs, since 1/5th is quite clearly already more than “a small part”.

Bob Meinetz's picture
Bob Meinetz on Feb 12, 2015 6:04 pm GMT

Bruce, in the case of Hawaii solar provides 20% of the electricity for .5% of the U.S. population, in a tropical island state, with the highest electricity rates in the country.

That’s quite clearly a small part of our energy needs.

Bruce McFarling's picture
Bruce McFarling on Feb 12, 2015 6:13 pm GMT

Hawaii in the article is cited at 12%. Its Australia that is cited at 20% penetration.

Bob Meinetz's picture
Bob Meinetz on Feb 12, 2015 6:32 pm GMT

Bruce, I’m so tired of renewables activists religiously padding their accomplishments that I almost don’t care anymore, but “grid penetration” is meaningless, and apparently refers to the number of Australian homes which have at least one solar panel installed:

Almost 1.25 million small-scale solar power systems were installed across the country by the end of 2013, meaning that around 3.1 million Australians now live or work beneath a set of solar panels.

In 2013, small-scale solar was responsible for 11 per cent of Australia’s clean energy generation and produced 1.62 per cent of the country’s total electricity.

https://www.cleanenergycouncil.org.au/technologies/solar-pv.html

Bob Meinetz's picture
Bob Meinetz on Feb 12, 2015 6:44 pm GMT

Shecky, a small number determined people can do a lot of damage quickly.

Putting the electricity of the entire state of Hawaii at the mercy of an unregulated, for-profit company is asking for it.

Hops Gegangen's picture
Hops Gegangen on Feb 12, 2015 7:18 pm GMT

 

I wouldn’t worry about Enphase in this regard. It just seems like an opportunity for hackers. But no worries, all the serious hackers are spending their time trying to get the nuclear plants.

 

 

Hops Gegangen's picture
Hops Gegangen on Feb 12, 2015 7:20 pm GMT

 

I liked that Tribalism article, didn’t you?

 

Bob Meinetz's picture
Bob Meinetz on Feb 12, 2015 8:17 pm GMT

Hops, distributed generation means distributed hacking opportunities, and less security than utility generation. No serious hacker is wasting his time on nuclear plants when a target this vulnerable is available.

But hacking isn’t even the main concern. A potential scenario: Enphase decides their services require an expensive maintenance contract, which HECO disputes. What options does HECO have? What options does Enphase have?

What kind of liability coverage does Enphase have if their microinverters take down Hawaii’s grid?

Bob Meinetz's picture
Bob Meinetz on Feb 12, 2015 8:23 pm GMT

Loved it. Really brought home how tribalistic thinking obscures important issues like ‘actual generation’.

Spec Lawyer's picture
Spec Lawyer on Feb 13, 2015 4:56 am GMT

Engineers find solutions.  Bob Meinetz manufactures imaginary problems.

Spec Lawyer's picture
Spec Lawyer on Feb 13, 2015 4:57 am GMT

Grrrr.  So mad.  Hate those people generating clean electricity!  How dare they!

Bob Meinetz's picture
Bob Meinetz on Feb 13, 2015 7:16 am GMT

Spec, don’t be mad. They don’t generate enough of it to bother with.

Robert Bernal's picture
Robert Bernal on Feb 13, 2015 4:13 pm GMT

Is that 20% at 100% capacity or is that 20% at 25% capacity? 1/20th or so of total power consumption is a start, but doesn’t address the costs of storage. If extrapolated to a global scale, that’s just 1/20th less excess CO2.

Oh, that’s just residential, I need to update the figure to be more like 1/50th less excess CO2 if scaled up to global proportions.

Jonathan Cole's picture
Jonathan Cole on Feb 13, 2015 5:42 pm GMT

Of course there are serious risks in this grid feeding solar scheme in which a third party, the inverter manufacturer starts intervening over the internet. There is, of course, the possibility of hacking the same portal that EnPhase uses which could seriously destabilize the grid. Since hacking is a very low cost form of war fare, I would be seriously concerned about those risks in a place like Hawaii (where I live) where the military is second only to tourism in the state’s economy.

This is why the entire scheme of having customers making capital investments that feed the grid (for a minimum monthly charge – i.e. free money for the utility) is really crazy. Remember, surpluses are zeroed out annually in net metering schemes. The customer thereby is supplying the utility with free kWhs, as well as no capital costs (for the utility) for the generating equipment, as well as reduced need for expensive transmission infrastructure (since the preponerance of solar-generated electricity is consumed onsite).

The fact is that this grid-feeding scheme is 180 degrees reversed from the optimal means of fully distributed solar with batteries that does not feed anything to the grid but only uses the grid as backup.  I have been building such systems and properly configured, they work out very well providing up to 99+% of electrical consumption from solar with the remaining coming from occasional grid backup which is automatically and invisibly switched in should the batteries reach a programmed low voltage set point. Another advantage of this approach is that no permission from the utility is required because there is no feed into the grid. Also the user is supplied with a high degree of energy security, virtually uninterruptible and much cleaner power, very different from what the grid supplies.

The vested interests in the utility industry should be in the business of providing secure, clean electricity to its customers and distributed PV with battery storage and no grid-feed is such a solution.

Spec Lawyer's picture
Spec Lawyer on Feb 14, 2015 1:12 am GMT

Glad you feel that way.  I expect you to stop your endless whining then since they really don’t matter, do they?  OK, Thanks.

Robert Bernal's picture
Robert Bernal on Feb 14, 2015 6:36 am GMT

Why do RE enthusiasts (almost) “always” put nuclear and coal in a like set?

Seriously, what will happen when solar gets up to full grid capacity – and there’s no more baseload left to power the night??? We can’t have coal, but we will use coal – anyways for the time being – a timeline that might have already taken too long

The threat of global warming caused by excess CO2 is a valid argument against coal – not nuclear. Therefore, nuclear should be included as one of the many solutions needed to counter fossil fueled depletion into an overheated biosphere.

Paul O's picture
Paul O on Feb 14, 2015 7:18 am GMT

And Spec Lawyer follows after Bob Meinetz, trolling him?

Spec Lawyer's picture
Spec Lawyer on Feb 14, 2015 8:09 am GMT

Criticizing may be the word you are looking for.  

 

Are you going to defend linking engineers solving a problem to 9/11?  Seemed worthy of criticism to me but perhaps it made some sense to you.

Spec Lawyer's picture
Spec Lawyer on Feb 14, 2015 8:12 am GMT

They don’t.  It is a very split view.  I have no problem with nuclear power other than it does need to be very carefully regulated and wisely deployed.  (Don’t use it in heavily seismic areas, don’t use it where a tsunami can wash over it, etc.)

Robert Bernal's picture
Robert Bernal on Feb 14, 2015 5:23 pm GMT

I want solar! But I’m not ok with cutting clean nuclear baseload to be replaced with NG (at night).

It’s not just this or that, it’s this and that (without the FF).

Bruce McFarling's picture
Bruce McFarling on Feb 15, 2015 3:41 pm GMT

Under that scenario, the energy sources available at night meet the nighttime demand, since its obvious that we would not have solar nameplate capacity at 100% of grid capacity without having other sources of energy providing the majority of the energy in the portfolio.

Bruce McFarling's picture
Bruce McFarling on Feb 15, 2015 3:45 pm GMT

This is a much more useful assessment of the statement … clearly, far from 20% “grid penetration” (as defined here) being “high”, in the Australian context it is clearly low.

Bob Meinetz's picture
Bob Meinetz on Feb 15, 2015 5:29 pm GMT

Spec, I understand it’s tempting to characterize criticism of a ridiculous claim like

Hawaii has a high level of solar grid penetration at around 12%. For context, Australia is already at greater than 20% and growing…

as “endless whining” when there is no factual defense available. Hawaii, and Australia, have no such grid penetration by solar – only roof penetration. Here, Hawaii’s actual solar generation is measured in hundredths of one percent:

So backed into a corner by the deficiencies and expense of their folly, renewables activists continue their assault on the messengers of bad news. Next…

Robert Bernal's picture
Robert Bernal on Feb 15, 2015 8:19 pm GMT

The object is to reduce fossil fuels at night, too. If a constant baseload is reduced in the day by solar, then more of something else will be required at night. This needs to be wind and nuclear or stored wind, solar and or nuclear, or just stored wind and solar without nuclear (and a little bit of biofuels and other RE sources).

Again, the object is to stop emitting excess CO2

Bruce McFarling's picture
Bruce McFarling on Feb 16, 2015 6:16 pm GMT

Night is when windpower availability is the strongest … when we look at the 40% of windpower supply that would be firm power if the MISO, BPA, CAISO and ERCOT regions were interconnected by cross-haul transmission, given the tendency toward a peak in the middle of the night, the portion that will be firm power during nightime hours will be higher.

So we may elect to treat solarpower on its own without cross-haul connection between distinct supply regions as a pure peak energy supply resource, but then adding substantial PV solar power to a RE portfolio containing substantial high quality windpower would be accounted as increasing the share of firm power available from the windpower: accounting rules on the treatment of the individual components of the portfolio won’t eliminate the increase in firm power in the portfolio as a result of combining energy supplies with as strong a negative covarience of supply over time as solarpower and windpower.

Even as a pure supply resource, when solar power is generated it either displaces fossil fuel power generation from the grid, or when all fossil fuel power has been shut down and it is displacing hydro generation to satisfy peak demand, it allows that hydro generation capacity to be shifted to other hours in the year. 

Bruce McFarling's picture
Bruce McFarling on Feb 16, 2015 6:23 pm GMT

On the first question: “Why do RE enthusiasts (almost) “always” put nuclear and coal in a like set?”

Part of it likely comes from the experience of nuclear advocates and coal advocates making similar claims backed up by similar stereotyped claims regarding RE.

Part of it comes from the faction of RE advocacy that originally emerged from anti-nuclear activism, who then added coal to their “enemies list” as the prospective costs of catastrophic climate change became more widely known.

And part of it comes from the fact that those who don’t put nuclear and coal in a like set, and who engage in internet discussion spaces are trained early on not to talk about nuclear, since raising the issue of nuclear is one of the easiest ways to sidetrack a discussion on the real world challenges and opportunities of policies to expand the roll-out of RE to displace the consumption of fossil fuels, so the discussion by RE advocates of coal and nuclear together strongly selects for those among the RE advocates that put the two in the same boat.



Robert Bernal's picture
Robert Bernal on Feb 17, 2015 6:36 am GMT

Concerning stereo typed claims, nuclear advocates (almost always) dislike renewables because of the obvious density and CF ratios. They can’t really see sources that have low CF as being a complete replacement for FF. Thus, they will downplay the potential of mass RE. I don’t want to do that *

I see nuclear, wind and solar as just the way things will play out. Wind, solar and EV batteries will become machine mass produced for “dirt cheap”. Modular molten salt (or similar) reactors must, too be made in a 21st century assembly line environment. Also, they will be meltdown proof (as per the laws of the physics of non water cooled non solid fuel). These two very important improvements should reduce intrinsic and regulatory costs, respectfully.

Anti’s should have deleted nuclear from their anti list as many scientists and environmentalists already have. Why? Because coal is obviously a far greater threat to the survival of the biosphere, and nuclear (as you have already seen in the many repeated messages) is less harmful than any other source per terrawatt hour (fact). Hanging on to the old movie hype from the 70’s (China syndrome) is no scientific reason at all to keep the anti nuclear train a roll’n (and what’s fashion got to do with it anyways).

RE advocates (should they need to be “trained”) would do the planet a favor by training themselves to including nuclear as one of their back up strategies. By not doing so, they actually make it harder to achieve the FF free objective.

97% (non nuclear) RE is going to be a lot more challenging than 3% FF (with nuclear). Why? Because “RE only” advocates consciously choose to simply delete a powerful planet saving solution! That is like me choosing to cut a greater portion of my family’s food supply! To make my point clearer, even the inventor of the LWR and the MSR (Alvin Weinberg) also set up a place to research solar energy (now called the NREL).

He said to KEEP ALL (non CO2 emitting) OPTIONS OPEN.

* No nuclear advocate is going to stop a billion solar roofs (and I like solar, too!) – however, no anti nuclear advocates need stop the clean energy from nuclear needed when the sun is down and the wind is slow. Why? Because 21st century nuclear will be cheaper than the RE bulk storage setup in a FF free planetary civilization’s immense energy infratsructure. Why? Because it requires less mass and land.

We will master CO2 free by demanding the big three – solar, wind and nuclear.

Robert Bernal's picture
Robert Bernal on Feb 17, 2015 6:55 am GMT

Based upon the history and extrolapation of energy sources (and mass produced goods), there is no monetary and no scientific reason to delete advanced 21st century, mass produced, meltdown proof, (possibly even spent fuel eating) reactors from the equation, other than regulatory costs caused by hyped up, unnecessary safety laws such as ALARA. NORM, radiological medicines and past fallout from much more intense sources of radioactivity proves that ALARA is unnecessary (also because the public is exposed to coal ash which concentrates “all that bad stuff”). Get rid of the unscientific ALARA parts of the regulatory costs to get the regulatory costs down. From there, the fact that nuclear requires less mass and land should intrinsically verify that advanced 21st century molten fuels, meltdown proof nuclear is a good way a 15 billion or so energy hungry, CO2 reducing planetary civilization – even with RE!

Spec Lawyer's picture
Spec Lawyer on Feb 17, 2015 12:31 pm GMT

Your irrational hatred is without bounds.  Roof penetration slight?

“Solar grid penetration” is not a technical metric.  It can mean the % of homes with solar PV or whatever the writer decided that it meant.  You, of course, conflate it with something it is clearly not (percent of electricity) and provide us with a long outdated graph.  And none of what you wrote has anything to do with my questioning your linkage of engineers solving problems and 9/11.  

 

But I guess “Haters gonna hate” as they say.   Keep it up, those kinds of bizarre rantings will help solar PV.  

Spec Lawyer's picture
Spec Lawyer on Feb 17, 2015 12:35 pm GMT

Unregulated company?  All inverter products coupled to the grid need to be approved by the local grid authority AND approved by local building departments.  And the work described in this story was with the cooperation of the local utility.

 

But I guess if you have no good arguments . . . just make up lies.  Keep it up!

Bruce McFarling's picture
Bruce McFarling on Feb 25, 2015 8:43 am GMT

“Capacity factor” is a purphee. Consider the capacity factor of wheat, corn, and similar harvesters, and whether we should refuse to build harvesters until they get their capacity factor closer to 80%.

When equipment is harvesting a renewable power source, it is misleading to analyze it as if it was a fueled power plant, so that a low “capacity factor” means that there is a larger fixed cost to be added on top of the per kWh fuel cost. With harvesting equipment, the cost of the equipment is financed by the expected average yield.

Indeed, a wind resource can be more valuable despite having a lower capacity factor, if its variability around its average yields is smaller … adding hours producing near the maximum yield is less valuable than a smaller boost in total energy output that increases the proportion of of the average yeild that is available as firm power.

Indeed, the benefit of tying together independent wind resources (such as the Northern Plains and the Pacific Northwest) is both the increase in the firm power produced and the decrease in the likelihood of generating close to maximum yield. There is a substantial benefit from the fact that maximum yields in specific wind farms in the Northern Plains are associated with weather systems that tend to move west to east, so that it is uncommon for all wind farms in the resource to be producing close to maximum yield at the same time …. and a substantial disadvantage to Pacific Northwest wind that producing within the resource tends to have a higher covariance.

Indeed, capacity factor is not even the be-all and end-all with nuclear power. Effectively operating nuclear in a semi-load following manner, as the French do, both necessarily reduces the capacity factor of nuclear, while at the same time increasing the value of its contribution to the grid.

 

Get Published - Build a Following

The Energy Central Power Industry Network is based on one core idea - power industry professionals helping each other and advancing the industry by sharing and learning from each other.

If you have an experience or insight to share or have learned something from a conference or seminar, your peers and colleagues on Energy Central want to hear about it. It's also easy to share a link to an article you've liked or an industry resource that you think would be helpful.

                 Learn more about posting on Energy Central »