We shouldn’t compare power sources based on nameplate ratings – watts by that? – After world

Misleading are the PR efforts that want people to feel good about the fact that weather-dependent power from wind and solar is “rooting” and “replacing” the traditional continuous uninterruptible mode of power generation.

Through Roland Stein Energy and Infrastructure Ambassador, Irvine, California

Tom Stacy Electricity Systems Analyst/Consultant, Ohio

Comparing nameplate ratings from different power generation sources is akin to using IQ as the sole or most appropriate measure of an employee’s worth to the company he or she works for… If everyone had the same level of health, skills and work ethic , it might be enough. But not us. And neither do different types of power plants.

For those of us who focus on the costs and benefits of different types of power plants within a grid system, it appears that there has been an orchestrated effort by the media, advertising and public relations – even government agencies – to mislead the public about the value Suggestion of wind and sun.

One of the most glaring examples is the continued use of the “nameplate rating” (generating capacity) of breezes and sunshine as a benchmark for value and comparison. The nameplate rating itself does not reflect the energy contribution or reliability of a power system.

In the 20th century, ‘nameplate valuation’ was a reasonable indicator of contribution to meeting peak demand whenever that peak may occur. Put another way, all common types of power plants could be turned on and operated – up to their “nameplate rating” – whenever they were needed (barring scheduled times for major maintenance or in the event of a small chance of an unexpected outage) because they were able to do their job manage fuels.

With these proven technologies, whose fuel availability is determined by human ingenuity and learning/adaptation, it is common to derate the nameplate rating by only about 10-15% to arrive at a “capacity value” or “system adequacy contribution” value (in reliable , need-based watts). This value for each power plant is totaled system-wide and the total expected to meet the maximum system demand (called peak load) is added about ten to fifteen percent more as a “reserve margin” to avoid possible power outages caused by unexpected or unanticipated generator failures be caused high demand.

The amount of reserve margin is a compromise between the risk of power outages (and other system reliability issues) and cost. Therefore, the “right sizing” of the system “adequacy” is important to keep electricity prices down because Power plants cost far more to build and maintain than all the fuel they will ever consume during their lifetime. Accordingly, Too many power plants are indeed too many because they are expensive to build and therefore rely on sufficient revenue from their productivity to pay for themselves and generate a return over several decades.

A 90 percent system adequacy contribution per watt of nameplate rating is fair and common across conventional types from coal to gas to nuclear. But wind and solar are different from “fixed” capacity technologies. Their ‘fuels’, sunshine and breezes, cannot be managed – ie constantly supplied and converted into electricity – and never will be. This is especially critical when demand is greatest. Therefore, they do not significantly replace the most expensive component of electricity costs: controllable power plants. Instead, they’re consuming market share, gross margin percentage, and revenue from the dependable fleet they can only pretend to replace.

Just as problematic as the inherent inability of renewables to produce electricity at times of peak demand is that these “irregular generators” often produce the most electricity when less electricity is needed by society, resulting in an undervalued market price for everyone power generators – sometimes lower than it costs them to generate (known as marginal cost) and well below the total cost of maintaining system adequacy when one takes into account loan payments, payrolls and other monthly expenses that all power plants must support.

for Wind and solar “nameplate rating” is not a measure of expected power production over time, nor of its contribution to system reliability. Yet, time and again we see government agencies, network operators and especially news media emphasizing GENERATION CAPACITY (nameplate rating) versus traditional generation technologies.

Using nameplate capacitance to compare technologies is misleading People believe that weather-dependent electricity can “replace” technologies that can manage their fuels when that’s not possible. This type of reporting and publicity is, intentionally or not, aimed at intermittent generation. It’s sad when it’s done by the media and public relations, and even worse when it’s done by a government agency.

However, in terms of cost comparison, the US Department of Energy’s EIA clarifies this in its annual Levelized Cost of Electricity reports, imploring:

The duty cycle for intermittent renewable resources, wind and solar, is not controlled by the operator, but dependent on the weather or solar cycle (ie sunrise/sunset). (and such) their leveled costs are not directly comparable to those for other technologies..” ……………………………. .

PJM, the world’s largest wholesale electricity market operator, appears to agree with this statement, describing the priorities in its recent renewable energy transition study: The correct calculation of the capacity contribution from generators is essential: A system with increased variable resources requires new approaches to adequately assess the reliability score of each resource and the system as a whole.”

This speaks directly to the importance of accurate comparisons of system adequacy contributions between different power generation technologies as the key metric of value – instead of the nameplate rating.

The correct two comparison metrics between intermittent and controllable power plants that should replace the use of nameplate rating are:

1) Contribution to system adequacy (in MW) and

2) annualized electric power generation (in MWh)

Unfortunately, as PJM suggests, the methods of estimating the contribution to system adequacy are also controversial. The most widely used metric is “the old approach” or ELCC (Effective Load Capacity). This metric would be useful if all generation technologies were symbiotic and not parasitic. In other words, ELCC does not take into account that wind and solar slightly affect the financial viability of the existing operational fleet that requires renewable energy, and uses the ELCC as a basis for calculating the system adequacy contribution of the “parasitic” renewable energy! In essence, the metric does not lend itself well to an energy mix in which competitive technologies cannot directly substitute for one another. ELCC subtly argues in circular fashion as renewable energy is politically favored and undermines the financial viability of reliable power plant investments.

A better way to estimate the contribution to system adequacy is to look at the recent historical generation patterns of renewable energy in the context of the load patterns and amplitudes they could serve, independent of the existing generation mix. We prefer one called “Mean of Lowest Quartile generation across peak load hours (MLQ)” suggested by Market Monitor in its 2012 SOM report on MISO.

Realistically, by this metric, the following shows both the nominal capacity (outlined, not color-shaded) and contribution to system adequacy (color-shaded) of the US electricity mix as of the end of 2018.

By using false bases of comparison between types of power plants, governments, market participants and image-obsessed corporations ignore prudent economics and physics and ignore the importance of power plants the idea of a cleaner, self-sustaining world that depends on the weather before supporting real priorities like an affordable, abundant, and reliable power grid system in line with FERC’s mission human bloom.

Renewable energy is only “footballing” because governments, market operators, utility regulators, and the like mislead Environmental, Social and Governance (ESG) factors – misguided only in that they do not take into account how the grid actually works, as discussed above – seek an unrealistic pace and impetus for the “energy transition”. These are driving modern civilization to achieve an economy like we had in the 19th century and before – the last time the world was “decarbonized”.

Ronald Stein, PE Tom Stacy
Ambassador for Energy & Infrastructure Power system economist



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