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View profile for Christian Leuchtenberg, graphic

Corporate Manager & Entrepreneur

GW versus GWh Excellent analogy to describe the fundamental illiteracy by many renewable energy advocates: "The first [mistake] was including energy storage in the comparison with nuclear. Of course, storage doesn’t generate anything — it just stores energy — so should be ignored when considering how much electricity we need to meet our needs every year. The second mistake was using gigawatts (GW) instead of gigawatt-hours (GWh). These cause a great deal of confusion in the energy debate, but they can be understood by using water as an analogy for energy. Gigawatts tell you the size of a pipe carrying water from a source, but not how much it carries each day, month, or year. If the source depends on the weather like the gutters in a roof do, then the pipe might be empty most days when it’s dry, but fill with water when it rains. Instead, gigawatt-hours is how you should measure energy needs, in the same way that the right way to measure ‘water needs’ is gigalitres. If you want to know how much water comes off your roof each year, you wouldn’t measure the width of your downpipes. In the energy debate, whenever you read GW, look for an ‘h’ at the end. Otherwise, you might be sold a pipeline with 80% of its capacity closed off." Courtesy of Zoe Hilton Link to article in comments.

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Taran Hughes

Sales, Pitching & Mindset / Coaching & Development for Founders / Mentor / Speaker / Author

3mo

Excellent point Christian, it helps to clarify these easily brushed-over distinctions. Thanks for the insightful article Zoe Hilton

In went to a conference recently where there were several vendors/OEMs pushing their power generation and energy storage solutions, but one stood out from the crowd. They had a display stand with graphics that declared that they had a system with "an 80KW battery". The first eye-catcher was the use of a capital "K" (absolute degrees Kelvin, after Lord Kelvin), instead of using a lower-case "k" (for kilo). BUT there is no such thing as an 80kW battery, as kW is power, not energy storage. Maybe they meant to say 80kWh, but you could only get that out of the battery in kW if you knew the C-rating (Peukert's Law) and I am certain that the battery looked like a standard VRLA C10 - so a power draw of maximum 8kW for 10 hours. OEMs should employ marketing people who know a little basic engineering about their employers business (:o) and then we could move on to clients, the public, and even politicians... or maybe that would be a bridge too far?

Johnston Clark

Design Engineer at ESCO

3mo

Interestingly, both GW and GWh are measures of energy flow.... I know, I know, technically GWh is units energy and GW is units of energy over time. But whenever we discuss GWh practically, we imply a time period - maybe a year, or a month, or a lifetime. So essentially, GWh is an average energy flow while GW is a peak. But since there are an unusual amount of hours in various timeframes - 8766 hours in a year, 24 hours in a day, it's hard to convert! Perhaps we should just drop GW altogether and describe GWh-peak instead?

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Bo Björkman

Affärsutveckling, DD-light, Ägarstöd. Ring 0722 160730

3mo

Very wise! And also remember about storing in batteries or elsewhere: If a solar plant or windpark is charging batteries in the daytime  - it can not at the same time produce energy to the grid! So, if you ”add” batteries to the system, you don’t add energy. You just move it around with extra losses and costs for the end user. When will they ever learn…

Bhargav Shukla, B.Eng,P.Eng

Working on Nuclear Power Plants, Nuclear research labs. Learning about Advanced Nuclear, SMRs, Green-hydrogen, Industry 4.0.

3mo

Totally agree. But one important point which is almost always missed is, every conversion (AC to DC to charge batteries and then DC to AC) to feed back into the greed has efficiency losses. You never get 100% back of what you tried to store. You loose 10-25% on each conversion, twice. Maybe in future technology improves losses reduce, but till then the capacity and efficiency is working against the intermittent power sources.

Poor technical literacy has always been an issue within the general public when discussing the difference between energy and power. This is why reliance on experts is needed but when the so-called experts are activists the facts and definitions get distorted and in many cases fabricated to suit the narrative.

Wait a second, "The Smart Energy Council" does not understand the difference between power (measured in watts) and energy (measured in watt hours)? Maybe they should call themselves 'The Not So Smart Energy Council". Seriously basic concepts of physics: Work is force times displacement ("distance") Power is work over time Energy is power integrated over time In other words, if you have a line graph of power output from a solar panel, the area between the line and the X-axis, that's energy.

Alexis Pilotelle

Energy expert - Technical advisor - Project lead

3mo

GW is a marketers metric, aimed at impressing non-technical people. GWh is the only metric that matter and must be displayed in front of peak load hourly curves to have any meaning.

Installed GW vs Actual GW.

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