solar energy

#saveARENA - There Has Never Been a More Critical Time for Renewables Research in Australia

I Have an Urgent & Important Message for You about The Australian Renewable Energy Agency

For those of you who follow my page, or have adventured here from beyond, it should be readily apparent to you that I’m an academic working in solar energy related research, more specifically in the modelling & forecasting of distributed PV power output.

To date, the majority of my work has been funded by ARENA, the Australian Renewable Energy Agency.  A funding body that has been absolutely crucial in supporting Australia as a global leader in renewable energy research over the past several years.

But ARENA is Under Imminent Threat

But right now, ARENA is under threat. The Coalition Government is planning legislation that will strip it of more than $1B of funding, and Labor are saying they won’t oppose it.

Let me explain to you why these cuts to ARENA research funding are a bad idea.

ARENA is currently funding nine university led research projects across Australia with more than $17M in funding, which are focused on partnering industry and researchers together to solve the major challenges we face integrating renewables into our electricity grid. What’s more, they intend to produce commercial outcomes valuable to the Australian economy.  (Isn't this exactly what the Australian government wants universities to accomplish? i.e. the National Innovation Science Agenda)

As an example, look no further than my own project, which received $1M from ARENA and raised $300k of industry cash to build distributed PV modelling and forecasting software for six distribution networks: ActewAGL, Ergon, Essential Energy, Western Power Horizon Power & Power and Water.

Perhaps this isn't quite enough industry partnership activity for the Coalition government?

Perhaps this isn't quite enough industry partnership activity for the Coalition government?

Don't believe the lies about a lack of value: ARENA has shifted toward driving commercially-focused outcomes

At the ANU, we're not just developing this distributed PV modelling technology to write some fancy publications.  We are delivering our software into the operations of our distribution network partners and creating a technology that will enable higher penetrations of solar to be added to the grid.  Going one step further, this software is being commercialised by an ANU start-up company, which we have already formed and is starting to complete this work now.  In the future, we hope to take this technology beyond Australia, and into other countries around the world.

Without ARENA funded research like mine, fewer solar PV systems will be permitted on our distribution networks.  Without research projects like the other eight industry-researcher collaborations in ARENA's R&D funding round, what other innovative technologies will Australia miss out on

Some Awesome Examples of Current ARENA R&D:

ARENA & Industry Funded: Drones that survey solar farms

ARENA & Industry Funded: Integrating solar thermal into alumina processing

ARENA & Industry Funded: Batteries & Solar PV into Apartment Buildings

If my project, and others like it, aren’t part of the “Innovation” agenda that the government wants, part of its “Ideas Boom”, part of the technology driven future of the Australian economy where it produces new ideas of global relevance, I don’t know what is.

If these projects aren't part of the "Ideas Boom"... I don't know what is!

We simply have a government that is demanding innovation on one hand, but clearly saying “just not for renewables” on the other.

What do we do about it?

Across Australia, our renewables powered people groups are springing into action, and our universities aren't letting this go down without a fight:

Solar Citizens has made it easy for you to tell your local parliamentarian to stop this madness

GetUp has put together a #saveARENA campaign where you can share your story about working on an ARENA funded project to your social media accounts.

I want YOU to join with me to #saveARENA

So I want YOU, to join with me, to tell our Parliament to #saveARENA. The legislation to cut $1B from ARENA is set to be introduced to Parliament early next week as part of an “omnibus bill”, so we must act now.

Let me be clear: There has never been a more critical moment for the future of renewables in Australia, or for our potential to be a leader in renewable energy technologies throughout the Asia-Pacific, and more broadly, across the globe.

Renewably Yours,

Dr. Nick Engerer

Be sure to retweet my twitter video:

And Follow #saveARENA on Twitter:



PhD Thesis: What I did, What I found, Why it Matters

Several years ago, I decided I wanted to write a Masters Thesis that didn't just sit on a shelf, collecting dust.  Call me idealistic, but I wanted to adopt a philosophy of "science off the shelf" 

[April 2016 Update: My PhD Thesis is now finalised! Download it here: Part 1  |  Part 2 ]

[download my submitted thesis - part 1]

[download my submitted thesis - part 2]

Back at the University of Oklahoma School of Meteorology, there was a running joke amongst graduate students that they could stick a $20 bill in their thesis, check back in 5-10 years, and find it still nestled between the pages, safe and sound.  While it was humorous, and mostly in jest, it reflected the mentality of postgraduate education/research work - what we were doing was mostly just to tick boxes & get our degree so that we could one day do something that mattered. In reality, our 'research' would sit on a library shelf, acquiring dust.

Yearly kWh production for a simulated 2kW Sanyo array in Oklahoma

Yearly kWh production for a simulated 2kW Sanyo array in Oklahoma

But I wasn't content to resign myself to this fate. I felt compelled to produce something that mattered, that would have real-world relevance.  So I brought on an industry partner, a local solar installer in Oklahoma, and put together a solar map for Oklahoma, not based on solar radiation - but on kWh hours of electricity generation, which immediately translates to payoff times and dollars. [download my M.S. Thesis]

It was a tremendously successful experience, and as I moved forward into my PhD project, I was very determined to not only maintain that approach, but to expand it.  Now, looking back, I can see that approach has paid off in great ways, which I'd like to share with you.  Because what I've discovered, what I've developed and what I am now positioned to do with the technology I created, is all highly relevant, commercially viable and ready to hit the ground running.

What I did and why

Australian PV installations by year, as provided by the Australian PV Institute

There is ~4GW of solar energy installed in Australia, which is dominated by ~1.4 million small-scale photovoltaic (PV) arrays.  These arrays are relatively small (average size 1.5kW in 2011, growing to 4.5kW by the end of 2014), and the vast majority of these installations are un-monitored.  This means that their minute-by-minute performance is not recorded.  In fact, the only information collected for most of these systems is the total quarterly production as reported on electricity bills.  Long story short, this lack of information limits the number of PV systems that can be installed in a given region (like here).

Measured PV power output, divided by that PV systems clear sky power output

Measured PV power output, divided by that PV systems clear sky power output

So what did I do about it? I developed a method for estimating the power output from many thousands of PV systems using a small selection of monitored PV systems (which report their minute-by-minute or hour-by-hour generation).  This method is called  “the clear-sky index for photovoltaics”, KPV. [read more]

Along the way, I had to do significant work in the field of solar radiation modelling, validating clear sky radiation models and developing a new type of solar radiation model fit to Australian radiation data (a "separation model").  I also had to show that my new method (using solar panels as a sensor network) was able to do the job just as well as professional grade radiation equipment.  

Pyranometer based methods versus KPV based methods.  The takeaway? Get the sites close enough (within 5km) and my new method is just as good as using a more sparse network of professional grade solar radiation sensors.  

It was also necessary to develop new quality control routines for the PV system power output data.  This type of data is messy, often provided by non-experts and hasn't been used in the way I've proposed before.  This was accomplished through the development of a new quality control routine called QCPV (now going through the review process in a major journal).

~200 solar PV systems installed in Canberra, which are reporting their data in real-time

Once I sorted out the quality control work, it became possible to work with data from many hundreds of solar PV systems, as well as scale my KPV method up to many thousands of systems.  So I forged ahead, using Canberra as a proof-of-concept, creating a city-wide distributed PV simulation of its 12,000+ embedded PV generators (based on December 2012 installation data).  

I then paired this simulation system with weather events that cause broad-scale, rapid changes in the power output of all of the PV systems at the same time [check it out].  It is these types of events which are the most likely to cause future grid stability problems.  The basic idea is that, when you have a wide-spread solar network, the negative effects of partly cloudy days are "smoothed out" by those systems being positioned over broad region, but during certain weather events, it is not possible to smooth out these impacts, because the cloud features are too widespread, sudden and thick.

"when you have a wide-spread solar network, the effects of partly cloudy days are "smoothed out" by those systems being positioned over large region, but during certain weather events, it is not possible to smooth out these impacts, because the cloud features are too widespread, sudden and thick"

What I did find?

Let me keep this as focused and brief as possible...

KPV estimates (color) versus measurements (black) under a positive ramp event

Firstly, I demonstrated that my newly proposed KPV method was much better than existing methods, showing that it was well-behaved under all cloud cover conditions, and performed well under positive and negative ramp events. [download publication][read blog post]

Next I found that for clear sky radiation models, operating in Australia, global clear sky simulations, are best computed by the Solis, Esra and REST2 approaches, while the Iqbal, Esra and REST2 methods are the most proficient clear sky beam models. [download publication][read blog post]

The Engerer 2 separation model at work (blue model estimates, grey observations)

 After that, I found that only the Perez separation model performed satisfactorily for high resolution (one minute) solar radiation data.  In response to this, I developed three new separation models, which gave slight improvements over the Perez model and greatly exceeded the performance of all other existing model techniques. [download publication]

Once that was handled, I compared radiation sensor based methods to my PV data based approaches, with a student project.  This study found that the approaches were equally as good for separation distances of 5km or less. Given that PV sensors are "cheap" (someone else pays for them) - this was a great finding. [download publication][read blog post]

Post QC KPV estimates, very tight correlation, great results

Then I dug into the development of the QCPV algorithm (quality control), demonstrating that the method I created can result in a 43% reduction in Mean Absolute Percent Error (MAPE) over the raw data. [pre-print coming soon]

Second to last, with another student project, we categorised the weather events that cause those large scale, collective changes in PV power output discussed earlier.  Positive collective ramp events (sudden clearing) were caused by Australian northwest cloud bands and radiation fog dissipation. Negative collective ramp (sudden cloud cover arrival) events were caused most frequently by the passage of cold fronts and thunderstorms.[download manuscript][read blog post]

Finally, I put it all together, with the city-wide PV simulation system, using it to simulate the changes in total power and energy output from these collective ramp events.  I was able, for the first time, to quantify (aka determine a representative number) the amount of power that (dis)appears on the electrical grid during these events.  For example, a thunderstorm event on 19 February 2014 removed 20.78 MW of power generation from the local grid over an 85 minute period, which equates to approximately 14.54 MWh of energy generation forgone over that period.  That's probably enough to change prices on the energy market - not very much, but as the solar installation numbers continue to grow, that influence will grow significantly.  

Here's the thunderstorm ramp event from 19 February 2014, along with some satellite imagery.

What is my overall conclusion?

The overall conclusion, is that the developed regional simulation system for distributed solar PV, made possible by an upscaling of my KPV methodology, represents a significant, unique and promising tool for scientific, engineering and operational purposes.  

In the simplest of terms: I built a very handy tool, with cheap inputs that can be run anywhere that solar PV systems are reporting their power output data.

Where next?

I have a full-time lecturer position ("professor" in the American use of the word) at The Australian National University, where I work in the Fenner School of Environment and Society (employed since July 2013).  I am using the freedom and security this position provides me with, to apply for funding to scale this simulation system up, Australia-wide.  I'll join it with the new Himawari 8/9 satellite data, and pair up with the energy market/utilities in Australia, in order to help large amounts of distributed solar to be added to the grid.  

You could say the future is sunny and bright (#punny).  And with HUGE amounts of solar being installed globally, the solar century is before us.  There are plenty of opportunities for this science to stay off of that dust shelf.  So I'd say, overall, this whole PhD thing has been a smashing success! Even if it was a bit of a wild ride.  I hope to have more exciting news soon - for now, I'll get back to working getting this simulator to run real-time in Canberra...

PhD Thesis Submitted!: An Extraordinary Adventure

4 years, and several lifetimes later, I'm submitting my PhD Thesis

[April 2016 Update: My PhD Thesis is now finalised! Download it here: Part 1  |  Part 2 ]

In October 2010, I got an email, advertising for a PhD scholarship in Solar Radiation & Energy with an organisation called CSIRO, at a place called The Australian National University, in a city called Canberra.  To be honest - I'd never heard of any of these things before.  But, having just made big progress on my M.S. thesis, focusing on solar energy, and not seeing any options in the U.S. in my field - I decided to a take a big chance, and apply for the position.

Several months, countless drafts of applications, and multiple scholarship awards later, I found myself with all my belongings narrowed down to 8 suitcases, and my (now fiancé), Teddi at my side, boarding a Qantas flight for Sydney.  It was June 2011, and I had no idea what I was getting myself into.

The Intellectual Property Bomb Goes Ka-Boom!

The Intellectual Property Bomb Goes Ka-Boom!


I dropped like a bomb into an Intellectual Property (IP) argument, where CSIRO wanted me to sign over all my rights, IP & future profits, with no research license, and The ANU was telling me and them, that was a rotten deal.  So by September, after plenty debate and conversations with lawyers, I found myself saying 'see ya' to CSIRO - and all those hard earned scholarship dollars, plunging myself into a black hole, devoid of financing, supervisors and a PhD project to undertake. But looking back, man, that was a very good decision

"I dropped like a bomb into an Intellectual Property (IP) argument..."

But, at the time, I sure did I feel like I was in big, BIG trouble. I had no scholarship money, $30k of tuition per year to pay, and I was thousands of miles from friends and family - not to mention I'd just dropped $4k to get my dog here!

But The ANU looked out for me.  I was awarded an APA and IPRS scholarship in October 2011, and I was back on my feet.  My supervisor, Frank Mills, was able to help me patch my first semester of fees together, and get me a living allowance to hold me over (thanks Steve Dovers!).  From these new scholarships, I was set for the next 3-4 years, to figure this PhD thing out.

So yeah, about this PhD thing - now I have no project, no data, no supervisory panel and no clue what the hell I'm doing in Australia.
Solar PV arrays as our sensor network? Our innovative idea.

Solar PV arrays as our sensor network? Our innovative idea.

But shortly after these scholarships appeared, so did new opportunities.  I met two inspiring senior scientists - who recognised my potential and respected my ideas from the very beginning: Professor Andrew Blakers (ANU) and Professor Bob Williamson (NICTA).  Together, we pioneered a new project, successfully obtaining funding from the Australian Solar Institute (now ARENA), for a two year project developing machine learning based distributed solar forecasting.  So from the ground up, I built my PhD project research team, its data, and all the analysis tools I needed. It was a heck of a lot of work and it challenged me in many ways, but it quickly became clear that the falling out with CSIRO, allowed something even better to evolve.  I was also empowered by people like Andrew, Bob and Frank - who gave me their respect and believed in my ideas, as we moved our new project forward. Upon reflection, I think that those two things are the best a young scientist could ask for.

So things were looking up! But I just couldn't help myself....

So, as if being a PI on a $850k grant project and doing my PhD wasn't enough, I decided to apply for a job opening for a lecturer at The ANU Fenner School of Environment & Society (my host institution).  It was early 2013, and I was bold & naive, with no idea what I was getting myself into.  I went up against people with CVs many pages long, boasting of 10 years more experience in the field.  But I fought hard, sold myself well, and played the youthful energetic kid with big ideas and a promising future angle.  And, well, somehow, I pulled it off, landed the job, and found myself lecturing & convening for two courses with 70-100 students each.  

"And, well, somehow, I pulled it off, landed the job, and found myself lecturing & convening for two courses with 70-100 students each." 
Accepting a Citation for Outstanding Contribution to Student Learning by an Early Career Academic in December 2014.

Accepting a Citation for Outstanding Contribution to Student Learning by an Early Career Academic in December 2014.

Surely I was mad.  A full-time teaching position & a big time grant project - when's the PhD going to be the focal point? Could I really pull this off? I was courageous enough to think that I could, and I strategised my way forward, quite successfully. Things were actually shaping up nicely!

But just as I was starting to piece it all together, and get my first PhD related publications sorted, and the first round of experiments for our project underway, life threw me the biggest freaking curveball it could think of.  In a tragic turn of events, along with the birth of our son, came a scary and rare cancer diagnosis for my beautiful wife.  

We were gutted. Overwhelmed. And the PhD quickly became the least of my worries.

Over the next 6 months, while teaching, PhDing and grant-doing - I had to fight, scream and campaign to get her to the top of the waitlist for a peritonectomy surgery.   From there, in March 2014, she underwent the 12 hour operation, and then spent 5 weeks in the hospital, recovering from the brutal battering her body had taken.  Once we came back home, it was a few months before she was back to 90% (do you ever make it to 100% after something like that?).

Wow, what ride! But both happy to be alive

So, cancer beaten!  Then, and maybe then, it was time to focus on the PhD?  But alas, I'd picked up another course to convene, in first semester, called The Blue Planet.  Now I was without a semester off from teaching, was seriously behind on everything, and I was feeling pretty wiped out from it all!

What had I gotten myself into? Teacher/Researcher/PhD-er/Family-Man - what a load to carry! 

Thinking big - my PhD developed a city-wide simulation system for distributed solar PV systems.

Thinking big - my PhD developed a city-wide simulation system for distributed solar PV systems.

But you know what? After you battle your way through something as crazy as cancer, where you face your biggest fears - you actually come out on the other side with a different perspective.  I realised, that after that ordeal - I wasn't actually afraid of failure like I had been before.  A PhD thesis, convening two courses and running a research project, it all was much less intimidating.  There was no more need to fear some distant failure, some imagined rejection, or any manufactured worries.  I'd been through the darkest period imagineable - and that perspective, really put me in a position of strength:  I wasn't afraid to dream big, take on large responsibility and slug it out one day at a time.  In fact, I began to see it as kinda fun.  A new freedom emerged - one where I wasn't held back by doubt, but was emboldened by believing in myself and a recognition of my own mortality. The time to go big, or go home, was now or never! 

So abandoning my philosophical promulgation, we can fast forward through 2014 and early 2015, and somehow, by April 2015, I was giving my final seminar. I had multiple publications under my belt, and it was time to do the dirty work - writing up my intro, conclusion and linking text.  My "PhD by compilation" was taking shape, and all I needed to do was put in the hours, and keep up that confident approach in the process.  

The death of my laptop, one month prior to submission...

The death of my laptop, one month prior to submission...

But, of course, life wasn't content to let me sail through though! I was constantly distracted by my efforts to get permanent residency (skills verification, english tests, medical exams, etc), my computer died in the final month of writing, and then my son decided to give our family the worst week-long gastro episode in existence.  And on top of that a new funding round emerged from ARENA which was far too good to pass up.  So instead of happily writing my PhD thesis in May-July 2015, I instead found myself preparing a grant application with multiple industry partners and a bit more of that bold, crazy thinking.  But nevertheless, I pulled it off, and here I am, just a few hours from submitting.

Upon reflection, I think that I've learned to tread carefully on the lines between (in)sanity!

So, in conclusion, when I submit that 200 page beast of epic proportions this afternoon at 3PM - I'll do it  with my cancer-punching wife by my side, ready to dream bigger than ever, with a resounding "Hell yeah! I did it!" in my heart. And if I can, amidst all that has happened.  You can too!

Thanks PhD, for the adventure of a lifetime! 

Oh, and good riddance too! :-)


PhD Final Seminar - City-wide Simulations of Distributed Photovoltaic Power Production

I've just successfully completed my PhD defence seminar, and am excited to share with you the results of my thesis project.

It sure is tough to fit a description of everything that I've accomplished over the past four years into an hour long seminar.  Well, in fact, it's impossible!  So much goes into a PhD thesis (dissertation), and only the author themselves will truly understand all the work that went into it.

But I think I've managed to do a good job getting the best of the best information into a manageable format - and I'll be able to share a video of the final seminar with you in a few weeks.  But for now, I'd like to get the slides up on the web, and post some of the simulation videos.

In the shortest summary possible: I've created a simulation system for Canberra PV installations, which uses a subset of monitored PV systems (approximately 80-160 systems, depending on the site availability/date) to simulate 12,500+ PV arrays.  The installed PV arrays are based on data provided by ActewAGL (local utility/distributor) about the rated capacity and suburb-level location of each install through December 2012. 

The heart of the simulation system is an application of the KPV methodology, which uses the power output from one PV system to simulate the performance of another nearby PV system. I've published a paper on the topic in Solar Energy  for those of you who are interested in the more technical side of things.

For now, I'm going to stop writing, post the slides and simulation videos, and let them speak for themselves.  I hope you enjoy them:

[download presentation]

Presentation Slides:

Presentation Videos: Simulations

Video of a a clear sky day for all PV systems installed in Canberra. The images you see are the result of using ~70 PV systems to simulate the remaining 12,500. 

Video of a high variability day where broad convective clouds moved through Canberra. 

Video of a positive ramp event resulting from fog dissipation in Canberra. The images you see are the result of using ~80 PV systems to simulate the remaining 12,500. 

Video of a negative ramp event resulting from convection moving into Canberra. The images you see are the result of using ~140 PV systems to simulate the remaining 12,500. 

The Impact of Weather Events on Solar Energy Generation: Recorded Presentation

Happy new year! As promised, here is a recorded version of our November 2014 presentation on weather events and solar energy generation in Canberra, Australia.

Please use the below recording from SoundCloud (press play!) and the below gallery of slides (click through them manually) to review our presentation.  There are two videos that will not work within the Gallery, but that's okay!  You can find them here, along with a summary of our research findings.

[download the presentation here]