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Critique of the 100 Percent Renewable Energy for New York Plan

100% Renewable Energy for New York State from Wind, Water and Solar. Really?

I feel compelled to respond to a paper that is widely referenced by anti-hydrofracking activists as proof that New York can move beyond fossil fuels and power 100% of its energy needs with renewables.  The WWS (Wind, Water and Solar) Plan for New York (Jacobson et al., 2013) is part of a series of papers authored chiefly by Prof Mark Jacobson from Stanford University that can be found here. The New York paper includes contributions from Cornell University professors Bob Howarth and Tony Ingraffea.  Jacobson attempts to makes the case that society can acquire all of the energy it needs for all purposes in a relatively short period of time from a combination of solar, wind, hydro and geothermal.  Jacobson is opposed to nuclear power and also opposes all hydrocarbon fuels whether bio or fossil based because of the contention that all CO2 emissions must be eliminated in order to prevent a catastrophic melting of the arctic sea ice.  The plan calls for an 80% conversion to WWS by 2030 and 100% conversion by 2050.  Unfortunately the plans are deeply flawed from a practical and technical perspective. 

Jacobson makes broad assumptions about the suitability of many different technologies and offers little evidence to back up his claims.  Such assumptions include the complete abandonment of hydrocarbon fuels for vehicles, heavy equipment, ships and planes and conversion to battery and hydrogen fuels.  No proof is offered that these new technologies can meet the performance requirements of existing machines.  Nor are any references from industry or the military presented to justify the technical feasibility of the claims.   Jacobson contends that some electric and fuel cell vehicles have come to market but that hardly meets the burden of proof that a century and a half of performance based industrial development can be converted over wholesale to new equipment that is not currently proven in real world use. 

A common flaw in the WWS model is the use of unproven technologies along with insufficient analysis of their land use impacts.  For example, wave devices, tidal turbines and enhanced deep well geothermal are included even though they are not mature technologies.  The WWS plan has virtually no discussion of the land use impacts of new power transmission or discussion of hydrogen storage and distribution.  Other writers have disputed Jacobson’s assumptions about electricity storage and economics here and here.  Debate over the feasibility of intermittent power sources to keep the grid running can be found here and here, a response to the critics by Jacobson can be found here.  A much more realistic model was produced this year by NREL in their Renewable Futures Study (NREL, 2012), they conclude that 80% of energy can be supplied by renewables by 2050; they detail emerging technologies but do not include them in the models, they do include biomass and accept that some uses of hydrocarbons cannot be replaced.

I am not going to attempt to cover every point Jacobson raises, but I will focus on some practical issues as they relate to New York.  Specifically, the wind and solar models are impossible as presented.  In all of the wind and solar cases (onshore and offshore wind, CSP and PV solar) capacity factors are overstated, land use is understated and public acceptance is never addressed.

The chart below is taken from the WWS NY paper and details the numbers of each type of device that would be required for the plan.  I added the yellow highlights.

 Energy sources for New York - WWS plan

Concentrated Solar Power – CSP

The most glaring defect in the entire model is the use of CSP, concentrated solar power, which is a thermal technology used in the desert and not applicable to New York.  I would challenge the authors to find any qualified engineers or developers who would certify these types of facilities for NY.  The authors call for 387 CSP plants rated at 100 MW each to be built throughout the state.  Each 100 MW CSP plant requires roughly 1 square mile of flat, unburdened land and requires the highest levels of solar insolation.  New York has the opposite characteristics: long, cold, dark winters and rolling hills covered in forests, fields and farms.  By the authors’ own figures, 327.3 square miles of land would have to be cleared to construct 387 of these projects across the state.   

 
Image

CSP plants in New York would most likely never function in the winter when snow and ice are common and the sun might not emerge for weeks at a time.  NREL, the National Renewable Energy Laboratory, lists seven southwestern states as being CSP compatabile: California, Arizona, New Mexico, Nevada, Colorado, Utah, and Texas in its Solar Market Report, 2010 (NREL, 2011).  The CSP map from NREL shows that New York is one of the worst places in the USA to attempt CSP.  The photograph of the Shams 1 CSP facility in Abu Dhabi shows what a modern 100 MW CSP looks like, and the landscape clearly does not look anything like upstate New York.

Photovoltaics – PV

Regarding solar PV, Jacobson overstates the capacity factor of their proposed farms in New York by cherry-picking an unusually high efficiency PV module, the SunPower E20, which is not reflective of the mean for the industry.  According to the sales literature, “SunPower E20 panels are the highest efficiency panels on the market today”(SunPower, n.d.) with 20% efficiency while the industry average for crystalline PV is closer to 15%.  So while the SunPower E20 modules do exist there is no discussion of module availabilities or specific costs and it is misleading to use them in the model because the scale of installations described in the paper would likely necessitate the use of common modules rather than select high performance modules.  It is like describing a huge vehicle fleet made from Ferraris rather than Fords.  Many PV farms globally use cheaper thin-film varieties that offer even lower efficiencies and require more land.   The authors state that the New York PV farms will have a capacity factor of 18% which is the average for the entire country (NREL, 2011) when New York is on the lower end of solar potential. 

In 2010, the typical efficiency of crystalline silicon-based PV commercial modules ranged from 14% for multicrystalline modules to 19.3% for the highest-efficiency monocrystalline modules (average monocrystalline module efficiency was 14%). For thin-film modules, typical efficiencies ranged from 7% for a-Si modules to about 11% for CIGS and CdTe modules. (NREL, 2011)

The WWS model describes 136.4 square miles of land devoted to photovoltaic farms in addition to the 327.3 sq miles of CSP for a total of 463.7 sq miles of land that must be cleared of existing fields, forests and farms to make space for the solar developments.  Ironically, Tompkins County, NY, home of Ithaca and Cornell University where some of the authors are employed is roughly the same size at 476 sq miles.  Does clearing an entire county’s worth of land to install underperforming solar technologies represent proper stewardship of the land?  Perhaps that land is better left growing plants that clean the air, soil and water, sequester carbon and provide crops and habitat.

Wind Onshore

The wind model presented is troubling because it assumes to utilize as many wind turbines as conceivably possible, basically placing turbines on every single hill with decent wind in the state without regard to people already living there.  Similar to the trick in the PV model, the authors choose particularly large turbines that allow them to overstate production. 5 MW turbines are used in the model when the norm around the US is 1-3 MW.  By choosing larger turbines the authors can project higher production and higher capacity factors than typically reported for New York because taller turbines reach higher into more consistent wind streams.  The Cornell Wind Study states that a 27% capacity factor is typical for NY (Hoerig & Smolenski, 2010) while Jacobson et al claim “30% or higher” (Jacobson et al., 2013) capacity factors.   

Taller turbines increase the environmental impact and spacing demands.  Larger turbines cast bigger shadows, longer wakes, make more noise and require bigger access roads for larger cranes and wider setbacks from homes and structures for ice-throw safety.  Jacobson consistently claims across his papers that turbines use very little land and that the space around them can continue to be used for farming.  This is true but ignores the impacts on residents, wind turbines make poor neighbors.  Land use requirements for access roads and power lines are also not sufficiently addressed.

New York State has fairly marginal wind resources compared to other parts of the country and installing over 4000 turbines for a total of 20,100 MW on shore dwarfs all expectations of the industry and state authorities.  To achieve 20,100 MW would require exponential growth of the industry over the coming decades and assumes total public acceptance that has not been demonstrated.

Wind Offshore

The numbers presented for offshore wind are truly astounding. 12,700 turbines at 5 MW each for a total capacity of 63,550 MW.  The authors do fairly note that there is not a single off shore wind farm anywhere in the United States in 2013, but that does not stop them from asserting that some of the busiest multiuse waterways will be packed to the maximum extent with a forest of very large turbines.  The available waterways in NY are the coasts of Long Island and parts of Lake Ontario and Lake Erie.  There is no discussion of impacts on shipping lanes, boating, fisheries, recreation or general public acceptance.  No discussion of bathymetric properties of the sea floor and whether the farms of the proposed scale are even technically possible.  Jacobson also never discusses wind shading and the principle that turbines block the wind from one another.  Densely packed wind farms as described in the models would have lower power production averages per turbine due to wind shading effects.

The proposed wind farm off Cape Cod for 130 3.2 MW turbines has languished for years due to sharp public controversy.  The notion that a proposal 100 times larger in nearby waters would be accepted by the public defies common sense.  This is not to say that there should no wind farms offshore, but we must be realistic with projections.  To offer another perspective: according to the Global Wind Energy Council, the total global offshore installed capacity in 2012 is 5,415 MW compared to the proposed 63,550 MW in New York alone. 

Conclusion

I hate to be critical of proposals for wind and solar because I hope these industries continue to grow, but the WWS plan lacks any technical credibility whatsoever.  It has been widely criticized by many writers and for good reason.  I only chose to add to the pile because I see the paper being hailed for political purposes by those with an agenda opposing drilling for natural gas.  Mark Jacobson has been making appearances on television claiming this is all technically feasible, well I have to disagree.

I share the authors concerns about global warming and pollution but the answer is not to take underperforming technologies and overbuild them to make up for their lack of performance, this is like having an unreliable car and buying two more so that you can always have one working when you need it.   New York is not a good location for CSP and is marginal for wind and PV, these technologies should certainly be utilized but they cannot be expected to provide the majority of New York’s energy needs.  On the other hand New York has vast resources of biomass and waste going unutilized that the WWS model rejects.  Garbage, sewage, farm waste and biomass can all be gasified and injected into the natural gas pipelines as carbon neutral or even carbon negative fuels that offer superior mechanical performance in existing machines.  These resources would not meet all of New York’s needs but they could make a sizable contribution and are mostly going unused today.

Performance cannot be ignored in the discussion of new energy solutions.  All too often advocates for renewable energy reduce the issues to academic equivalency equations that assume fossil fuels can simply be replaced by alternatives without examining the mechanical requirements involved.  Society moved from biomass to coal to petroleum to natural gas because at every step competitive performance advantages were achieved.  Historically, the military and industry have been the arbiter of these conversions and the ultimate proving grounds have been the battlefield and the marketplace.  If proposed energy solutions do not enable the military to fight and win battles or industry to get heavy work done more effectively then the proposals will not be adopted.  It is well worth noting that Jacobson et al never detail combat vehicles or heavy equipment like those required to manufacture and install wind and solar devices.  There is a large body of literature on clean energy futures that are far more thorough and credible than the WWS study, this study does not pass even a cursory examination.

Maps provided by NREL, http://www.nrel.gov/gis/maps.html

Hoerig, C., & Smolenski, K. (2010). 2010 New York State Wind Energy Study.

Jacobson, M. Z., Howarth, R. W., Delucchi, M. a., Scobie, S. R., Barth, J. M., Dvorak, M. J., … Ingraffea, A. R. (2013). Examining the feasibility of converting New York State’s all-purpose energy infrastructure to one using wind, water, and sunlight. Energy Policy, 57, 585–601. doi:10.1016/j.enpol.2013.02.036

NREL. (2011). 2010 Solar Technologies Market Report, (November).

NREL. (2012). Renewable Electricity Futures Study (Vol. 1).

SunPower. (n.d.). SunPower E20 / 435 SOLAR PANEL.

Content Discussion

Dan Mantena's picture
Dan Mantena on November 17, 2013

Hi Ed,

I recently attended an energy seminar talk which included Mark Jacobson where he strongly advocated for this 100% renewable future.

After the talk I asked him what role storage plays in the future grid.  He said our studies have shown we don’t need any storage in the western US grid.  After that I realized he knows little to nothing about power engineering and is just advocating for renewables which can be quite annoying.  His idea might be to overbuild our generation system by 3x of actual demand so that we have energy during most hours of the year which is very inefficient.  

I really don’t understand how he has any credibility to his name in the scientific community.  Do people agree with him and let him publish papers because he is a professor from Stanford?  He does not understand how slow energy transitions are in the world.  The large natural gas capacity we are building currently will last us for the next 40-50 years.  No one is going to turn off their natural gas plant before it reaches its lifetime unless it proves to be uneconomical.  His plan is good for climate change but questionable for the economy and national security of the US. The fact that I find so frustrating is that he has such a high role in society and he is feeding people incorrect information.

 
John Miller's picture
John Miller on November 17, 2013

Ed, this is a very thorough and common sense evaluation of the WWS New York (renewable power) Plan.  Besides being overly optimistic on renewable power capacity factors, land-use requirements and other local-Resident impacts, these types of studies most often do not do a reasonably good job of including or estimating the financial impacts; capital, maintenance and operating costs and the ultimate cost increase impacts on future Consumers’ power rates.  For a variety of reasons, these and many other authors or development groups (such as NREL) assume that achieving 80-100% renewables is feasible based on existing technologies (or anticipated near-future developments), and rarely acknowledge the need for baseload nuclear and/or peaking natural gas power required for continuous power grid supply-demand balancing/operations and reliability.

Agreed, biomass conversion to syn-fuels is definitely going to be a significant part of the solution to displacing fossil fuels in the future, but as I am sure you are aware, even this renewable will likely only be a part of the ultimate lower carbon energy generation solution in the future.

Keep up the good work of helping folks better understand what the more feasible solutions will be to ultimately reducing our carbon footprint in the future.

Bob Meinetz's picture
Bob Meinetz on November 17, 2013

Dan, thanks for sharing that experience. Overbuilding is indeed Jacobson’s basic premise for avoiding the storage issue; he feels we can coordinate enough diverse areas on the renewable map, and use smart tech to shuffle generation into and out of play. The deal-breaker is something that Jacobson et al do not address, and in fact is impossible to address: we can never have enough storage or enough planning to rely on renewables, because letting the lights go out is not an option. That means an entire dispatchable infrastructure must be ready to take over when unusual weather conditions create a danger of that occurring.

In California the Tehachapi Wind Farm is building storage, at a cost of $55 million, which will be enough to power the state on a typical afternoon for six seconds. One full day of storage would cost hundreds of billions of dollars.

What is absolutely prerequisite to even attempt to answer the question of how to address climate change is a realistic assessment of possibilities.

Robert Bernal's picture
Robert Bernal on November 18, 2013

It’s a great plan… if we can machine mass produce storage for like ten times cheaper than lead acid… and if we are willing to deal with all the extra powerlines from the sunnier regions.

Biofuels should not even be considered because we need all that to go back into the ground for natural CO2 sequestration and soils preservation.

I keep asking people “What is cheaper on a global level, 500,000 sq miles of solar and storage or nuclear?”. It’s best that we don’t base the future of energy on the past so we must develop an inherently safe form of nuclear (and try to develop renewables and their storage via profit free machine automation?)… and let the cheapest win!

Ed Dodge's picture
Ed Dodge on November 18, 2013

With my critique I was intentionally focusing on the practical engineering, not on the economics, not because economics are unimportant but they get written about a lot and can be abstract.  My problem with the 100% renewables strategies in general is the assumption that electricity and fuel are directly fungible because they are all energy, but it is really not the case.  Wind and solar simply do not provide the same type of functionality of storable fuels, at any price.  If we want to be serious about replacing coal and petroleum then we need a superior fuel that outperforms functionally as well as economically.  The only thing I see is natural gas as a direct replacement for all uses of coal and oil.  And since natural gas is simply methane, and methane is highly renewable we can actually use the natural gas infrastructure to carry renewable natural gas as well.

Robert Bernal's picture
Robert Bernal on November 19, 2013

I’m wondering how hard is it to “make” renewable methane. Is it easier than making cheaper batteries?

Ed Dodge's picture
Ed Dodge on November 19, 2013

There are lots of ways of producing methane easily.  Anaerobic digesters break down manure, sewage and food waste into biogas which is 60-65% methane and can be readily upgraded into pipeline quality natural gas which is 95% methane.

Gasification is used thermally breakdown dry carbon based materials: biomass, garbage and coal into synthesis gas which is a blend of carbon monoxide and hydrogen (CO-H).  Syngas can be converted into methane through various methanation processes.

All of these technologies are well established and commercially proven.  Synthetic methane is given a variety of names: biomethane, substitute natural gas, renewable natural gas and others.  All that really matters is that the product is CH4.  CH4 is arguably the most versatile, abundant and renewable of all hydrocarbons.  And I would say that it is easier than making batteries. 

Robert Bernal's picture
Robert Bernal on November 19, 2013

Lots of nature. But biofuels require more land than solar. And coal gasification isn’treally clean. Also, it seems more limited than all out solar and wind. But some one else effectively argued the point that switch grass can be used and still ids good for the soil, even after much use. So every little thing counts as long as a newbreed of aneric digester doesn’t wipe out the forests.

I’m gonna go all out for solar, wind and nuclear because excess CO2 requires lots of extra energy for clean up.

Ed Dodge's picture
Ed Dodge on November 19, 2013

Its not a matter of biomass replacing all fossil fuels, there is certainly not enough biomass for that.  But biomass and these other resources can be combined with conventional natural gas and in doing so lower the fossil carbon content.

Wind and solar are limited by their low capacity factors, intermittency and lack of storage.  I fully support moving ahead with nuclear, but it will take time to manage the political and technical challenges.  

In the short run, to replace coal and petroleum you need a fuel that can do the same jobs better and cheaper.  Right now natural gas is the only proven option that can power big machines like ships and mining equipment better than oil and coal.

Bruce McFarling's picture
Bruce McFarling on November 19, 2013

The puzzling point to me is the notion that combustion of carbon sequestered from the atmosphere over the previous year or over the previous five years is somehow more carbon emitting than solar or wind. I have encountered this in comments on some of my own essays on 100% renewable energy systems … that somehow biofuels do not count even if their feedstock is raised sustainably. It seems that people imagine that if I were to dip a cup into a bowl half full of water and pour it back in, and repeat that process enough time, the bowl would eventually overflow.

The other point is intrinsic to the framing of a 100% renewable energy system for New York State, which is that renewable energy cross-haul on a continental or subcontinental scale will allow for a more efficient renewable energy portfolio, due to the fact that wind and solar energy availability from different resource areas are less volatile in combination than they are individually.

Rick Engebretson's picture
Rick Engebretson on November 19, 2013

Always glad to see another biomass researcher, Ed. Perhaps there are some tricks that will support your thinking.

First, we might ask how to convert a dead tree or grass to size? We know high pressure will fragment the cellulose because a sharp saw blade is just applied force divided by a very small area. Pressure (force/area) can be created quite easily these days up to roughly 60,000 psi; the yield strength of mild steel. Modern hydraulics works and the day and night temperature differences are quite an engine.

Second, if you watch a wood fire burn you will see the hot glowing coals evaporate the wood into fuel that ignites when mixed with air. One might speculate if we expose the wood to red hot temperatures without air we will still have a fuel. Destructive distillation of biofuels, and nutrient rich biochar have become an area of interest. An interesting possibility is the use of 6000 degree blackbody radiation (sunlight) as a source of process heat; solar biofuel.

I would mostly leave the microbiology in the septic tank. We are trying to make people the primary beneficiary of bioenergy. Many alternative approaches to consider.

Doug Payne's picture
Doug Payne on November 21, 2013

 

 

 

 

 

Jim Stack's picture
Jim Stack on November 21, 2013

My home is 110% Renewable. I also run my 100% electric vehicles from Solar. I use the excess from the GRID and help the GRID during the day with extra energy and at night by taking and storing the excess. Hydro could provide the base load power so we don’t need any other sources.

Nuclear is the most expensive power ever made, uses millions of gallons of water and produces deadly waste. If anyone thinks it’s good let them put a system on their home and prove it.

COAL is so Flintstones, makes tone of waste, uses water and make more pollution than anything else. It’s less than 40% efficient and can’t be turned down when need drops at night.  Just mining it is very polluting.

Natural Gas is only available since Fracking. We hit Peak NG in 2004 and were importing, now we want to export while fracking kills our water and environment.

Fossil and Nuclear are all loosers. Boiling water is so last century while we have zillions of Photons pouring down each day right when we need it most. The Millions of Electric Vehicles being sold can provide V2G Vehicle to GRID for fraction of any other storage.

 

Doug Payne's picture
Doug Payne on November 21, 2013

Jim Stack,

There are a lot of people like you nowdays. I am so pleased to see your comment here, full of optimism and wisdom. I would focus on the positives of what you are doing and the technologies of the future, rather then talking about Fred Flintstone.

I happenned upon a chat room on a site called paltalk. The room is called “off grid living”. They would love to have you. Pop in there some time.

There are some technological solutions to all of the criticisms of 100% green energy.

There is no technical solution for an atmosphere of 700PPM CO2.

So you are at the cutting edge of the practical path to avoid it. You are one of the first on a train we all have to catch.

Doug Payne's picture
Doug Payne on November 21, 2013

Bob

In power grids all over the world, there are fossil fuel, gas power stations costing billions of dollars and they sit there doing nothing. For instance many 300MW+ gas stations sit in grids and they  run <1% of the time and half of that may well be testing.

Modern technology makes it possible to replace that security blanket, with systems at less then 10%  of the installation cost. I urge you to research this a little.

Einstien said in the 1950s that all our energy needs could be achieved with clever utilization of atomic energy. He was referring to cars, homes and virtually everything. He said we will have to move away from buring coal and oil. What most people don’t realise, he was referring to the atomic energy sent here by the sun.

Robert Bernal's picture
Robert Bernal on November 22, 2013

I believe the price increases that require subsidy to low income are caused not necessarilly by the little tiny amount of expensive wind and solar that has been added to the mix, but of the huge amounts of the possible nuclear that has been taken away (by efforts that cut advanced nuclear development decades ago). By now, they would be near the end of the capital pay off and would be soon providing cheap electricity, even cheaper than coal once carbon taxes are applied.

There is no reason why melt down proof gen IV designs (some of which have been already proven such as the molten salt reactor) should not be re-developed and scaled up. Lives are depending on it… and so is renewable energy…

Solar is not that bad. It is coming down in price and does not need to be stored (that’s what nuclear is for).

MSR’s should be developed to match “run of the mill” Brayton NG generators, keep it at baseload and add the NG for peak (when solar and wind are “down”). Electricity needed to make all the renewable energy parts, solar panels and electric car batteries should be provided by this grid variable friendly setup.

Robert Bernal's picture
Robert Bernal on November 22, 2013

Yes, every “age” needs to eventually be replaced.

Coal prevented complete deforestation and saved the whales. Now it’s on par to destroy all that and so much more (because of the effects of excess CO2).

Meltdown proof nuclear (in the closed cycle) for baseload and for powering the machine automation of cheaper solar and EV batteries is the next step (we don’t want too much fission products lasting for like 300 years) The almost unlimited energy from nuclear will most probably be needed to clean up the excess CO2, as well.

Ed Dodge's picture
Ed Dodge on November 22, 2013

Jim,

I would like to hear more about your home.  How big and how many people living in it?  What is your electricity production and consumption? Where are you located?  How do you heat your home?  What kind of car do you drive and how far do you drive every day?

Where I live in upstate NY I know folks who are off the grid, but they are very concious of reducing their electrical demand, they also typically heat their homes with wood.  These are generally single family homes in good solar locations.  Wood burning is not sustainable or clean, deforestation is a proven result of overuse of wood fuels and many people continue to suffer health problems in the developing world from burning wood for cooking indoors.   I heat my home with wood, but I have seven acres of forest just for myself which is hardly a model for society as a whole.

My house deep in the woods can’t take advantage of solar unless I were to clear a lot of trees.  And as population density increases, ie people living in apartments in the cities, the ability to use solar as primary power decreases.  PV is very useful, but it simply does not provide a lot of power, and for energy intense uses PV falls short.  I suspect your electrical vehicle is not a work truck loaded with tools and materials driving sixty miles each direction to job sites.  For heavy work vehicles natural gas is a great solution.  And we are not running out of methane, not now or ever as we can manufacture it.

 

Rick Engebretson's picture
Rick Engebretson on November 22, 2013

I’m not aware of any deforestation due to proper fuel use. I am aware of huge areas of deforestation due to conversion to cropland, pasture, and urbanization. Use of large machinery, herbicides, fire, goats, and concrete will kill a forest. Same for draining wetlands for water used elsewhere.

If anybody knows where smart forestry is practiced and is shown unsustainable, please advise. If anybody knows how we will manage CO2, water, biodiversity without forest management, same. I’m convinced most of you have never seen how big a tree is, or how much energy is stored, or how fast a tree grows, or how many trees there are, or that trees die. I live in an area of Minnesota that NASA illumination maps compare with North Korea for darkness. There is a lot of forest out there that needs management, and deserves better understanding.

It is hard dangerous work, with too many armchair experts.

Bruce McFarling's picture
Bruce McFarling on November 23, 2013

Though wind is not limited in the short run by lack of storage, as in the short run we would be looking toward 20% wind penetration, and we have sufficient storage available in place in existing hydropower capacity for 20% wind penetration given a relatively modest investment in transmission capacity, much of which investment is already in progress. Intermittency is lower when solar and wind are combined than for either individually, as well as lower when multiple solar and wind resource regions are connected by long haul transmission than if we were to attempt a “go it alone” strategy with an individual interconnect or portion of an interconnect, as contemplated in the NY Renewable strategy.

The limits of wind and solar are in the longer term, and with respect to those limits storable biofuels and fuels generated from surplus power generated by the volatile energy supply components of the RE portfolio are quite promising to provide the required 20% to 30% dispatchable renewable energy component. A country such as Australia that has sufficient high quality Concentrated Thermal Solar resource to provide substantial intra-day dispatchable power may not require substantial biocoal / biogas / RE-powered hydro fuels (whether methane or ammonia) … but with so much of the high quality resource for CSP in the US located in the Southwest, it seems like it may be an essential component for a 100% RE portfolio in the eastern US.