Update, 2018-12-15
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Thanksgiving in 2018 was cold, but it was also sunny. That means the 150,000 solar installations in Massachusetts could delivery on their combined 2.7 GW promise and actually delivered 1.5 GW towards the 15.5 GW needed. Of course, production varied during the day. With additional solar and wind, and additional storage, generation could have been banked to offset the “duck curve” seen.
What’s striking is that, despite the availability of wind and solar resources, wind generation is, at times curtailed by direction and order, since neither ISO-NE nor utilities have a way of routing some excess power or storing it when they don’t need it. This has been identified as the surest sign of a grid which is falling behind the needs of modern distributed generation. Called Do-Not-Exceed orders, they are a vestige of an attitude of central command-and-control grid management, rather than planning and moving to a design where the grid more-or-less manages itself, based upon technical window-ahead signals and predictions. Note ISO-NE has championed a market system to achieve this. That is a form of feedback control system, but it is one having appreciable lags in response. If the system errs in its predictions, whether on demand or on supply, there are energy assets wasted or shortfalls in provisioning. Such errors are why conventional grid managers put so much emphasis upon “dispatchable resources”.
People who can move predominantly off the grid, whether now or in the next 10 years, can insulate themselves from this kind of administrative fragility. Some can’t, and need to live with it, at least until the Massachusetts Department of Public Utilities and their Governor see the need to modernize.
Thanksgiving wasn’t the only banner day. Here was 21st April 2018:
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Our own solar generation on those days looked as depicted in the following figures. Note there are two PV arrays reported, a 10 kW one, and a 3.4 kW one. They of course both feed our home and the neighborhood grid, but as they were installed at different times, are monitored separately. The 3.4 kW wasn’t online for 21 April 2018, yet.
The difference in generation intensity is primarily due to length of solar day and tree shading at low sun angles in Autumn. On Thanksgiving, many of our tree still had leaves on them. I’ve included a look at 2ne August for contrast.
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Update, 2018-12-15
As @dumboldguy pointed out in a comment, while the contribution of renewables to Massachusetts electrical energy looks impressive in these figures, the “Y axis of the first graph begins at” 9 GW, not zero. This shows how far Massachusetts needs to go to get any appreciable amount of renewables for electricity. And, moreover, it also shows, as I responded, how silly it is to claim that renewables are destabilizing the grid in Massachusetts: They are barely making a dent.
Also, and something which @dumboldguy did not say, but I insist upon saying again, the Massachusetts public’s dislike of onshore wind essentially means they are opting for natural gas as an electricity-generating source and this, necessarily, means they are opting for the new pipelines that come with it. That’s because:
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The differential in price between offshore wind and the price of onshore and the slightly higher price of natural gas means that kWh for kWh, offshore wind won’t compete with natural gas any time soon. Here’s the Lazard Levelized Cost of Energy (unsubsidized) analysis from 2018:
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I have annotated it to point out price of onshore wind versus offshore, and various gas generation prices. Note that solar is expensive (see top), without subsidies. Note, too, that because the grid is antiquated in Massachusetts, using wind and solar means relying upon peaking gas generation plants, if only for part of the time. Note how expensive they are, ignoring greenhouse gas effects.
ecoquant
667 per centimeter : climate science, quantitative biology, statistics, and energy policy 
Click to access IEEE_QER_Intermittent_Renewables_Storage_October%203%202014.pdf
https://www.ieee-pes.org/pes-nerc-renewables-task-force
There are many book-length reports for policymakers and such available here:
https://emp.lbl.gov/research/renewable-energy
https://emp.lbl.gov/
such as:
https://emp.lbl.gov/publications/impacts-variable-renewable-energy
and
https://emp.lbl.gov/publications/retrospective-analysis-benefits-and
and
https://www.publicpower.org/periodical/article/lbnl-report-examines-value-northeast-offshore-wind
and
https://www.utilitydive.com/news/gas-plants-or-renewables-new-lbnl-study-helps-utilities-compare-the-risks/441579/
LBNL has a group that has looked comprehensively at the economics of household PV, including what it does to house prices upon resale.
Apart from the intermittency of generation, there is little extraordinary about PV and wind generators. Conventional generation at scale has intermittency issues, too, and the present grid can handle that, as long as only a fraction of the total generation is intermittent.Beyond that, new grids, policy, and controls are needed. Although the problems there are at larger scale, my impression is that there are few original problems on power grids that haven’t already been encountered and solved in several ways by power system engineers … The ones that design the power supplies for computers, buildings, electric buses, and smartphones. The challenges of designing power systems for smartphones are truly extraordinary.
While I am not familiar with on-the-line power engineering, I am familiar with aspects of power system dynamics and stability involving control theory. Nevertheless, there are details of power delivery pertaining to power quality, such voltage and frequency drift, which are, in many end user applications, considered important. These often demand special services.
Anyway, for a textbooks, I recommend:
Grigsby (ed.), Power System Stability and Control, https://www.taylorfrancis.com/books/9781439883211
and especially Vasca and Iannelli (eds.), Dynamics and Control of Switched Electronic Systems, https://link.springer.com/book/10.1007%2F978-1-4471-2885-4
Hope this helps, but, then, I’m not a professional power system engineering or even EE. I get into the maths.
ecoquant,
thanks for the lazard link but i was looking for something of a book length treatment that would cover the basics.
@oarobin, the best reference is Lazard, a link to which I just included in an update to the post. They also do a levelized cost of storage analysis. They consider unsubsidized costs to start, and then subsidized, as well as cost of capital.
To see the effect of being able to do onshore wind as I just mentioned,note that two utilities have, on their own, decided to move to full renewables. But they have access to lots of onshore wind.
The only shortcoming of Lazard is that they do not do projections, although, unlike the U.S. EIA, they have recently begun to present historical cost declines in solar, wind, and storage.
Thanks, by the way, for your kind remarks.
ecoquant,
off topic plea for resource pointers.
i have long followed your posts over at ATTP and Taminos blogs and thought them interesting.
being a newbie to these “energy debates” on the role / capabilities of renewables vs fossil fuels vs nuclear i find the claim – counterclaim back and forth confusing.
can you point me to some solid resouces on the basics of analyzing energy sources, their capabilities, the current state of energy generation (worldwide) and projected future growth?
this would be very helpful to me.