Climate Change

From: Watts Up With That

By: Charles Blaisdell PhD ChE

Date: April 13, 2022

Where have all the Clouds gone and why care?

The earth’s cloud cover has long been an important puzzle in climate change.  Cloud cover has many types and varies significantly from year to year.  Ground records of global cloud cover over 40 years have shown a 0.41%/decade decrease in cloud cover. (A 37-year European only study found a 1.4%/decade decrease).  In the last 20 years, Dübal and Vahrenholt CERES satellite has data that confirmed the ground observations of cloud cover decrease and a correlation with earth’s net incoming energy flux, albedo, and earth’s temperature rise.  Albedo is derived from the Latin word for white, a high albedo, 1.0, is totally reflective of sun light and a low albedo, 0.0, is totally absorbent, with albedo the lower the hotter.  These few pieces of data beg some questions.   When did cloud cover start to decrease?  Is it cyclic?  How much of the of the observed global warming, GW, can be attributed to cloud cover reduction?  What is causing it?  Will the decrease stop?  And, why should I care?  Let’s start with why should I care, every 1% reduction in cloud cover could account for 1.6 W/m^2 (about 0.8’C) increase in earth’s net incoming energy flux – a significant part of all the observed GW.  If this decrease started a 100 years ago and the current decrease is 0.4%/decade the total decrease over that time could be 2% or 3.2 W/m^2 (estimated 1.6’C GW) – more than the observed 2.2 W/m^2 (1.1’C GW).  Sumerville and Gautier in 1995 summarized that if the cloudiness of the earth decrease it would have a much greater effect on GW than doubling the CO2.  In 1995 no data existed that suggested the cloud cover or relative humidity was changing over time.  That is no longer true. (continue reading)

Where have all the Clouds gone and why care?

The wind and solar generation systems installed in the US have been installed in the most favorable locations available, for obvious reasons. However, as wind and solar generation are expanded toward a renewable plus storage generation infrastructure and electric demand increases as the result of electrification of transportation, residential, commercial and industrial appliances and equipment, wind and solar installations will have to be extended into less favorable locations.

US EIA Electric Power Monthly reports the annual average capacity factor of US wind installations as 35.3%, with capacity factors ranging from 28.2% - 41.1% seasonally. The annual average solar photovoltaic capacity factor is reported as 24.2%, with capacity factors ranging from 14.9% – 33.3% seasonally. These capacity factors would be expected to decrease somewhat as installations expanded into less favorable locations. However, capacity factors for offshore wind installations are expected to be somewhat higher than for onshore wind, in the range from 40-50%.

Solar installations in the northern tier of the US would be expected to have lower capacity factors during the Winter as the result of the lower sun angle and snow accumulations on the collector surfaces. Wind turbines operating in colder climates would require heating of the blades to avoid snow and ice accumulations, which would impose parasitic power consumption on the turbine generating capacity.

However, the greatest expected impact on renewable generation capacity factors would likely be the need to overbuild generation to have excess capacity available to recharge storage when storage replaces fossil generation as grid support when renewable generation fluctuates and during periods of low/no wind and solar availability. Significant renewable generation capacity would be in surplus during periods of good wind and solar availability when storage is fully charged.

The analysis of the need for storage is somewhat simpler for solar than for wind. On a clear day, solar collectors might generate at rated capacity for as long as 8 hours. However, they will predictably generate no electricity for the remaining 16 hours of the day. Therefore, any loads they serve would have to be served from surplus wind availability or from storage. Some solar generators are installing 4-hour storage to serve the daily peak in the late afternoon, after the solar system stops generating. However, that storage capacity must be recharged from excess capacity during the 8-hour solar generating day.

Wind generation is less predictable throughout the day and its fluctuations and interruptions must be met from storage, which must also be recharged from excess capacity during the day.

The increased investment resulting from generation overbuilding and the requirement to provide short and intermediate duration storage to smooth fluctuations in renewable generation output and long-duration storage to support the grid during periods of low/no wind and solar availability will also substantially increase the cost of the renewable plus storage grid. However, these additional costs are unavoidable if the grid is to be stable and reliable and not subject to catastrophic failure. Renewable generation developers have been able to ignore these issues in the mixed renewable and fossil grid, but will be unable to do so going forward.

From: Ventura Photonics

By: Roy Clark

Date: February 20, 2022

REJECT AR6

The Sixth IPCC Climate Assessment Report (AR6) should be rejected outright because it is based on the use of fraudulent climate models. This fraud comes from the underlying assumption of radiative forcing in an equilibrium climate used to construct the models. Such models are fraudulent by definition, before a single line of computer code is written. Climate science has now degenerated past scientific dogma into the quasi-religious ‘Imperial Cult of the Global Warming Apocalypse’. Scientific reason has been replaced by blind advocacy. There is no ‘climate crisis’. Eisenhower’s warning about the corruption of science by government funding has come true. The entire multi-trillion dollar Ponzi or pyramid scheme built on these fraudulent modeling results needs to be shut down and those responsible should face the legal consequences of their activities.

SUMMARY

The recently published draft of the latest UN Intergovernmental Panel on Climate Change (IPCC) Report, Climate Change 2021: The Physical Science Basis, [IPCC, 2021] the contribution of Working Group 1 to the Sixth IPCC Climate Assessment (AR6) should be rejected outright because the report is based on the results from fraudulent climate models. This fraud comes from the underlying assumption of radiative forcing in an equilibrium average climate used to construct the climate models. These models are fraudulent by definition before any computer code is even written. AR6 is a continuation of the climate modeling fraud that started with the invalid assumptions that were made when the first computer climate models were developed in the 1960s. All of the equilibrium climate model results used by the IPCC since it was established in 1988 are fraudulent.

There are at least three separate parts to this fraud. First there are the invalid climate equilibrium and related assumptions that originated in the nineteenth century. These led to melodramatic prophecies of the global warming apocalypse and became such a good source of research funding that the scientific process of hypothesis and discovery collapsed. Second, there was institutional fraud related to ‘mission creep’ within various government agencies. For example, NASA was established to put a man on the moon. There was no provision to shut it down after that mission was accomplished. Climate modeling provided alternative employment for some of the NASA ‘scientists’ with nothing else to do. The climate fraud was firmly established at NASA by 1981. Third, there was a deliberate decision by various outside interests, including environmentalists and politicians to exploit the climate apocalypse to further their own causes. There was no single person or event that created the climate fraud. There was a gradual transition from the invalid hypothesis of an equilibrium average climate to the massive multi-trillion dollar pyramid or Ponzi scheme that we have today. (continue reading)

REJECT AR6

The electric utility grid requires instantaneous balancing of demand and supply. Historically, most fluctuations on the grid were the result of changes in customer demand. However, as intermittent renewable sources of generation are added to the grid, changes in the output of wind and solar generation sources increase the complexity of grid balancing. A recent report by Elexon regarding grid balancing in the UK illustrates the rapid increase of grid balancing costs as the intermittent renewable fraction of generation increases. The report suggests that this trend will continue as the percentage of intermittent generation on the grid increases.

The principal source of grid balancing generation in the UK is natural gas combined-cycle generators, as it is in the US. Battery storage is currently a minor source, though it is planned to grow considerably. However, it is critical that battery storage growth exceeds the rate of reduction of capacity of the other sources of grid balancing generation, particularly natural gas generation. This is especially important because of the anticipated growth of electric demand resulting from the electrification of transportation, residential, commercial and industrial energy consumption.

As the transition from fossil generation to renewable generation proceeds, the contemporaneous transition from fossil grid balancing to storage grid balancing would increase the renewable generation capacity required to support the grid. Storage would support the grid during periods of low/no wind and solar generation, but would require the availability of renewable generating capacity in excess of the contemporaneous grid demand to recharge the storage batteries so that they are ready for the next requirement for grid balancing.

The excess generating capacity required would be a function of the duration of the grid balancing demand on storage resources and the period over which storage must be recharged. For example, the “wind drought” which affected the UK and parts of Europe in the fall of 2021 lasted for approximately 10 days. In that case, the grid balancing was accomplished with fossil generation in the UK and nuclear-generated electricity imported from France. However, in a renewable plus storage grid, the balancing generation previously provided by fossil generation would have to be replaced by withdrawals from storage. A requirement to replace the electricity drawn from storage in such a 10-day period over the following 10 days would require a doubling of renewable generating capacity, half to serve the contemporaneous demand of the grid and the other half to recharge storage, assuming no further demands on storage for grid balancing over that period.

It has been common in the US grid to maintain a 20% capacity reserve margin relative to peak demand, should one or more generators need to be taken offline for maintenance or repairs. In a renewables plus storage grid, both the renewable generation and the storage system would have to include such a capacity reserve margin. A requirement to function through a 10-day period of low/no wind and solar and to recharge storage over the succeeding 10-day period, with a 20% capacity reserve margin, would require renewable generating capacity approximately 2.4 times peak demand on the grid.

From: Watts Up With That

By: Larry Hamlin

Date: March 29, 2022

34 Years of Flawed, Failed & Grossly Misrepresented Global Sea Level Rise Speculation

For decades climate alarmists in the UK, EU and U.S. have been making flawed and failed exaggerated claims regarding accelerating global level sea level rise being caused by increasing man made CO2 emissions as one means of politically bullying the world’s nations into mandating immensely costly, bureaucratically onerous and completely ineffective global CO2 reductions from these nations.

The flawed CO2 reduction schemes in the EU and UK have created significant declines in energy availability and reliability because of these nations excessive reliance on unreliable, nondispatchable, backup power reliant and costly renewable energy. These politically contrived emissions and energy incompetent policies have resulted in greatly increasing energy costs for EU and UK nations that negatively impacted their economies while significantly increasing their dependence on energy from other nations.

This energy dependence includes greatly increased needs for natural gas, petroleum and coal supplies obtained through other nations and especially from Russia which (before sanctions) provided about 40% of the EU’s natural gas energy as well as being the EUs main supplier of crude oil (27%) and hard coal (49%). This data and other information concerning the EU and UK self-inflicted climate alarmist driven energy and economic debacle is addressed here, here and here.

The EUs efforts to build additional liquified natural gas terminals to wean itself off Russian gas is estimated to take at least three years with existing available import shipping facilities already maxed out. Renewables would take even longer. Any new LNG cargoes will have higher costs than the existing Russian pipelines. EU policy makers are stuck with politically damaging options including rationing energy and using more coal which means dumping climate goals. When push comes to shove emission reductions will take second place to economic survival with this huge energy and emissions policy turnaround already underway and being led by Germany. (continue reading)

34 Years of Flawed, Failed & Grossly Misrepresented Global Sea Level Rise Speculation

This commentary suggests a reporting format for the renewable plus storage demonstration discussed in the prior two commentaries.

• Renewable Demonstration
• Transparency

This proposed demonstration project has several important objectives:

• Create a unique renewable plus storage service area
• Force design of a standalone capable renewable plus storage grid
• Highlight the critical nature of electricity storage in this grid
• Highlight the evolving status of grid storage technology
• Highlight the sensitivity of this grid to daily and seasonal weather variations
• Document in and out storage losses in real storage systems
• Document inversion system losses in real grid operation
• Demonstrate the advantages of storage at the generation sites
• Establish the real cost of electricity in a renewable plus storage grid
• Document the number and magnitude of grid emergencies
• Document the effects of the transition to electric vehicles on the grid
• Document the effects of the transition to electric appliances and equipment
• Document the effects of the transition to electric industrial processes

The information collected using the form above should be available to the general public on a website designed to provide easily understandable access to information on the performance of the renewable plus storage grid demonstration, since this is the intended future national electric grid. The project should be treated as a learning experience for grid designers and operators, but also for customers served by the grid.

It is regrettable that the demonstration must begin with largely pseudo-storage, rather than physical storage systems. However, it is not possible to design and operate a reliable grid based on renewable generation without storage. The proliferation of renewable generation with conventional generation support has created the impression that renewable generation system design can be simple and inexpensive. However, in a fossil-free generation system, additional renewable generation plus storage must replace the conventional backup currently relied upon for generation when wind and solar generated electricity is not available in sufficient quantities to meet the contemporaneous demand of the electric grid.

From: Climate Etc.

By: Judith Curry

Date: March 17, 2022

A ‘Plan B’ for addressing climate change and the energy transition

I have a new article published in the latest issue of International Affairs Forum.

The topic of this issue is Climate Change and Energy.  Mine is one of twenty papers.  A range of topics are covered.  My article is the least alarmed among them.  You may recognize several of the authors, which include Don Wuebbles and Bill McKibben.

Here is the text of my article:

A ‘Plan B’ for addressing climate change and the energy transition

Climate change is increasingly being referred to as a crisis, emergency, existential threat and most recently as ‘code red.’  Climate change has become a grand narrative in which manmade global warming is regarded as the dominant cause of societal problems. Everything that goes wrong reinforces the conviction that that there is only one thing we can do prevent societal problems – stop burning fossil fuels. This grand narrative leads us to think that if we urgently stop burning fossil fuels, then these other problems would also be solved. This sense of urgency narrows the viewpoints and policy options that we are willing to consider in dealing not only with our energy and transportation systems, but also regarding complex issues such as public health, water resources, weather disasters and national security.

So, exactly what is wrong with this grand narrative of climate change?  In a nutshell, we’ve vastly oversimplified both the problem of climate change and its solutions.  The complexity, uncertainty, and ambiguity of the existing knowledge about climate change is being kept away from the policy and public debates.  The dangers of manmade climate change have been confounded with natural weather and climate variability. The solutions that have been proposed for rapidly eliminating fossil fuels are technologically and politically infeasible on a global scale. (continue reading)

A ‘Plan B’ for addressing climate change and the energy transition

I believe that the demonstration project described in the previous commentary should be conducted rigorously and transparently, with broad website access to hourly, daily, monthly and annual data.

The first step in this process would be detailed documentation of the generation resources serving the demonstration zone by type, capacity and capacity utilization over a historical reference period. This information would provide the basis for the design of the renewable plus storage system.

The next step in the process would be the initial design of the renewable plus storage system to replace the existing conventional, dispatchable fossil generation resources. This would include designation of the types and capacities of the wind and solar generators, plus designation of the capacities and delivery rates of short, intermediate and long duration storage to be installed or simulated by pseudo-storage.

The demonstration would commence once the solar and wind generators and any actual storage capacity had been installed and tested. The new wind and solar generators plus the existing non-fossil generation would be used to meet the contemporaneous demand of the grid and to charge both actual and pseudo-storage.

The demonstration website would report the quantity of electricity generated by each type of generation both in absolute terms and as a percentage of rated capacity, as well as the electricity in both actual and pseudo-storage and its deliverability.

Failure to satisfy contemporaneous grid demand with the demonstration zone resources would be compensated for by measured deliveries from conventional fossil resources, but would require immediate determination of the renewable generation resources and/or storage resources required to avoid such emergencies in the future, and the costs of acquisition and installation of those resources.

Transparency would also require that all renewable generation and storage resources installed in the demonstration zone be capitalized at their full cost, with no federal or state incentives of any kind. The full costs of land acquisition, site preparation and facilities installation would also be included. Actual storage facility costs would be documented and pseudo-storage costs would be set equal to wind and solar generator costs for systems with equivalent delivery capacity times the number of days of capacity stored. Such calculated costs would be replaced with real facility costs when real storage equipment becomes commercially available. This approach would assure that customers in the demonstration zone pay the real costs of the electricity they consume.

All emergency generation and pseudo-storage electricity deliveries would be priced at the full cost of providing the service on an emergency basis. This pricing could be negotiated between the demonstration zone management and the utilities positioned to provide the service. These costs should be based on the cost of the next increment(s) of generation for the supplying utilities, since this is the electricity which would have to be generated over and above the supplying utility’s contemporaneous grid demand.

These approaches to the demonstration should assure that the demonstration zone facilities would be designed to be a reliable and flexible renewable electric system and that the electricity costs in the demonstration zone would representative of a renewable plus storage grid on a national scale.

From: A Walk On The Natural Side     By: Jim Steele     Date: March 12, 2022

Separating Science from Pseudoscience for Floods and Extreme Precipitation

I believe it is essential that at least one large scale demonstration of a completely freestanding renewable plus storage powered grid be conducted under carefully controlled conditions. This demonstration should begin as soon as possible to gather the information necessary to assure that a national renewable grid is reliable. Regrettably, such a demonstration would require installation of long duration storage, which is not currently available commercially.

However, the demonstration could begin by requiring that the renewable generation in the demonstration zone be isolated from eternal sources of backup power and required to deliver surplus electricity to external grids which would function as pseudo-storage. The electricity delivered to pseudo-storage could be returned to the renewable demonstration zone in quantities equal to the quantity of electricity “stored”. The management of the renewable demonstration would be required to specify the storage capacity they required to achieve renewable grid reliability and could deliver only that quantity of electricity to pseudo-storage and draw only that quantity from pseudo-storage.

The demonstration could permit the demonstration zone managers to “install” additional generating capacity and pseudo-storage as required to compensate for lessons learned during the demonstration. The reasons for addition of additional generation and storage, as well as for the selection of particular generator and storage types should be carefully documented.

The demonstration managers would be able to import electricity from external sources if required to avoid demonstration grid failure, but would then be required to install additional generation capacity or contract for more pseudo-storage to avoid a repeat of the imminent grid failure condition. The demonstration managers should not be permitted to deliver electricity outside the demonstration zone, other than to pseudo-storage.

The demonstration zone should not include hydro generation capacity, since it is not broadly available. Nuclear generation capacity in the demonstration zone should approximate the 20% share of generation nationally, if necessary by limiting electricity delivery from nuclear generators to the demonstration zone. The demonstration zone should be located near the coast, so that offshore wind generation could be included in the generation mix as it becomes available.

A demonstration of this type would rapidly identify essential design characteristics and illustrate design flaws in a way that current attempts at demonstration and deployment have failed to do. Actual electricity storage should replace pseudo-storage as it becomes available.

No special provisions for environmental impact statements or siting approvals should be permitted, so that the establishment and development of the demonstration zone mirrors the actual experiences expected during the national transition to a renewable plus storage grid. Again, this approach would quickly identify issues which would affect the national transition. Issue resolutions implemented to facilitate the timely rollout of the demonstration should be available for all future environmental and siting issues, not limited only to the demonstration.

It might be ideal to site the demonstration zone in the metropolitan Washington, DC area to assist agencies of the federal government and federal legislators to understand the various issues with a renewable plus storage grid in real time and work to resolve them in a timely fashion.

From: National Review

By: Bjorn Lomborg

Date: March 3, 2022

Turning Down the Climate-Change Heat

The fixation on warming is harming the planet

We live in an age of fear — particularly, a fear of climate change. One picture summarizes this age for me. It is of a girl holding a sign say­­ing “You’ll die of old age. I’ll die of climate change.”

This is the message that the media are drilling into our heads: Climate change is destroying our planet and threatens to kill us all. The language is of apocalypse. News outlets refer to the “planet’s imminent incineration,” and analysts suggest that global warming could make humanity extinct in a few decades. Recently, the media have informed us that humanity has just a decade left to rescue the planet, that 2030 is the deadline to save civilization, and that we must radically transform every major economy to end fossil-fuel use, reduce carbon emissions to zero, and establish a totally renewable basis for all economic activity.

The rhetoric on climate change has become ever more extreme and less moored to the actual science. Over the past 20 years, climate scientists have painstakingly increased knowledge about climate change, and we have more — and more-reliable — data than ever before. But at the same time, the rhetoric that comes from commentators and the media has become increasingly irrational. (continue reading)

Turning Down the Climate-Change Heat

From: The Global Warming Policy Forum

By: Michael Kelly

Date: March 2022

Achieving Net Zero: A report from a putative delivery agency

Preface

I imagine that I have been appointed the first CEO of a new agency set up by Her Majesty’s Government with the explicit goal of actually delivering Net Zero by 2050. I asked for a few months to be able to scope the project and to estimate the assets required to succeed. This is the result of that exercise, and the consequences that flow from the scale and timescale for meeting the target.

Executive summary

The cost to 2050 will comfortably exceed £3 trillion, a workforce comparable in size to the NHS will be required for 30 years, including a doubling of the present number of electrical engineers, and the bill of specialist materials is of a size that for the UK alone is comparable to the global annual production of many key minerals. On the manpower front we will have to rely on the domestic workforce, as everywhere else in the world is working towards the same target. If they were not so working, the value of the UK-specific target is moot. The scale of this project suggests that a war footing and a command economy will be essential, as major cuts to other favoured forms of expenditure, such as health, education and defence, will be needed. Without a detailed roadmap, as exemplified by the International Technology Roadmap for Semiconductors that drove the electronics revolution after 1980, the target is simply unattainable. (continue reading)

Achieving Net Zero: A report from a putative delivery agency

A reliable electric grid supplied predominantly or exclusively by intermittent renewable generators such as wind turbines and solar arrays would require massive energy storage to provide continuous power to the grid when the output of the wind turbines and solar arrays was fluctuating, inadequate or unavailable.

Some renewable electricity providers have installed batteries capable of compensating for output fluctuations of several minutes duration. More recently, some renewable electricity providers are planning installation of battery storage systems capable of delivering power to the grid for up to 4 hours.

NREL estimates that the current cost of such 4-hour storage systems is approximately $350 per kWh and that it is expected to decrease to approximately $150 per kWh by 2050. Based on these estimates, 4-hour storage for a 2.5 MW wind turbine or solar array would cost approximately $3,500,000 and that cost would be expected to decrease to approximately $1,500,000 by 2050. This compares with the estimated installed cost of a 2.5 MW wind turbine or solar array of approximately $3,200,000.

It is important to remember that the 10 MWH available from the storage system must first be provided by the wind turbine or solar array. US EIA Electric Power Monthly reports that a 2.5 MW wind turbine would have produced an average of 21.2 MWh per day in 2020, while a 2.5 MW solar array would have produced an average of 14.5 MWh per day. Therefore, the electricity stored in the batteries would constitute half to two-thirds of the total electricity output of the generators on an average day. In this example, the storage system would be capable of providing more electricity to the grid in 4 hours than the renewable generators did in the remaining 20 hours of the average day.

While these 4-hour storage systems would provide some ability to tailor electricity supply to demand load shape, they would add little to electricity supply reliability during periods of low/no wind and solar availability. Storage systems designed to provide continuous electricity delivery to the grid during multiple hours or days of low/no wind and solar generation are referred to as long-duration energy storage. California has recently solicited bids for such systems with a capacity of 50 MWh or greater and a delivery time of 8 hours or greater. While such systems would represent a significant advancement of the state of the art, they fall far short of the requirements for a storage system which could continue to supply electricity to the grid through a “wind drought” such as the recent ten-day event experienced in the UK.

Form Energy claims to have developed an iron/air storage battery capable of continuously delivering electricity to the grid for up to 150 hours, or about 60% of the duration of the UK wind drought. Such a storage system for a 2.5 MW wind turbine would require a storage capacity of approximately 130 MWh, which would first have to be provided by the wind turbine. Initial estimates place the cost of such a system at approximately $20 per kWh, or approximately $2,600,000, not including installation and land costs.

From: Watts Up With That

By: David Coe

Date: February 26, 2022

Climate Change, an Emergency, or Not?

The Impact of CO2, H2O and Other “Greenhouse Gases” on Equilibrium Earth Temperatures

"The cries of Climate Emergency are becoming ever more strident. We are bombarded on a daily basis from almost every section of the media with stories of impending doom unless we take immediate and decisive action to prevent a climate catastrophe. This action includes the rapid adoption of a “zero carbon economy”. But what does this actually mean?

Carbon is the atom which, above all others, is the basis of life on this planet. Its unique atomic structure enables it to combine with other atoms to produce the amazing variety of complex molecules necessary for all forms of life.

Of course ,what is meant by “zero carbon” is actually zero carbon dioxide, the molecule which has been “fingered” as the demonic source of global warming, now known as climate change, climate emergency, climate catastrophe or whatever the next superlative tag can be attached to the word climate.

Just how does carbon dioxide come to be the instigator and chief cause of global warming? I say chief cause, because other gases are also in the frame as contributors, namely methane and nitrous oxide, for which the global agricultural sector is shouldering the blame, because of methane liberated by cattle and nitrous oxide from fertilisers. The story goes like this." (continue reading)

Climate Change, an Emergency, or Not?

The Administration goal of a fossil free grid by 2035 would require that the renewable portion of grid energy supply be supported by additional renewable generation plus electricity storage. The hourly, daily, monthly and seasonal variability of renewable generator output would no longer be supported by conventional fossil generation.

The US Energy Information Administration (US EIA) Electric Power Monthly reports an average solar photovoltaic capacity factor for calendar year 2020 at 24.2%, with a monthly average range from 7.1 – 33.3%. Monthly average capacity factors for 2021 through October range from 6.3 – 30.2%. Capacity factors are highest in the Summer and lowest in the Winter.

A 2.5 Megawatt (MW) solar collector array would have produced at an average rate of 0.605 MW (2.5 * 0.242) per hour, or 14.52 MWH per day in 2020, with a monthly average rate ranging from 0.1775 – 0.8325 MW, or 4.26 – 19.98 MWH per day. These averages mask the fact that solar output could range from 0 – 2.5 MW uncontrollably throughout the day and from day to day and would be zero at night. Therefore, on an annual basis and applying a typical utility capacity reserve margin of approximately 20%, a 2.5 MW solar array could be relied upon to provide approximately 0.15 MW (0.1775/1.2) if combined with storage capacity capable of storing electricity at a rate of up to 2.5 MW and discharging electricity at a rate of approximately 0.15 MW during a typical day.

A 2.5 MW solar array would also require storage capacity of approximately 15 MWH for each low/no solar day which might be experienced at the solar array location. The recent “solar drought” in the UK and parts of the EU lasted for approximately 10 days. Using this experience as guide, a 2.5 MW solar array would require storage of approximately 150 MWH capable of continuous discharge at a rate of 15 MWH per day. This storage would have to be recharged at the end of the period of low/no solar. However, the output of the solar array would be required to meet contemporaneous grid demand, so additional generating capacity would be required to recharge storage. Assuming that recharging the storage over the same number of days over which it was discharged would be acceptable, another 2.5 MW solar array would be required. More rapid recharging would require additional solar array capacity.

The availability of long-term, low-loss storage would permit the reliable capacity of the solar array and storage system to be increased from the 0.15 MW calculated above to approximately 0.51 MW [(0.605/0.1775) * 0.15)]. However, such long-term, low-loss storage is not currently commercially available and its likely cost, based on current technology, would exceed the cost of the additional solar array capacity required to increase output in the lowest output month of the year to the average annual output of the 2.5 MW solar array.