Posts

45. How Cool Is Coal?

  How Cool Is Coal? (Originally published 6/16/22) It’s interesting to try and imagine how our children will explain to their grandchildren what it was about burning coal that inspired such fierce allegiance even after we already had less expensive alternatives. Sure, it fueled the industrial revolution–we’ll give it that glory–but what, besides nostalgia for those coal-fired locomotive trains maybe, could it be?? Spoiler alert: you won’t find out the answer here, because we really don’t know. Coal’s un-glorious features are manifold and varied: environmental destruction from mining, mine-workers’ lung diseases, greenhouse gas emissions from mines, greenhouse gas emissions from coal burning, public health impacts of coal burning, health and environmental impacts of coal industry waste, to name the obvious ones.  Let’s start with the mines. Underground mines were responsible for 8% of U.S. methane emissions in 2019 (U.S. Energy Information Administration). Surface mines strip t...

44. You Just Might Find - You Get What You Need! (Demand response)

  You Just Might Find - You Get What You Need! (Originally published 6/2/22) By far the most popular “Yes, but…” about wind and solar electricity is, “Yes, but what do you do when the wind don’t blow and the sun don’t shine? We need power when we need it, and we need it, well, all the time.” This used to end the discussion.  But not any more.  Advances in technology, including electricity storage and “demand response” technology, are on target to realistically address the intermittency issue at scale. In the storage arena, battery arrays, hydroelectric plants and pumped hydro will provide part of the answer, storing energy when more is being produced and putting it back onto the grid as needed. But another approach is demand response . Simply put, demand response is a way of controlling demand to respond to supply.   Electricity needs to be used or somehow stored at the instant it is generated.  Conversely, when electricity is called for, it needs to be sup...

43. A Short Course in Greenhouse Gases

A Short Course in Greenhouse Gases The various “greenhouse gases” can be a source of confusion: carbon dioxide, methane, nitrous oxide, refrigerants (f-gases), sulfur hexafluoride, water vapor….How should we budget our concern about each of these? What is their relative importance in the strategy for addressing atmospheric warming? Back when some of us were young we learned all about the greenhouse effect as a GOOD thing: carbon dioxide (and a few other gases) in the atmosphere insulated the earth so all life could thrive. Now students have to learn about too-much-of-a-good-thing. Since the beginning of the industrial revolution the amount of these gases has steadily increased as a result of human activity. Primary among the greenhouse gases is carbon dioxide (CO2), but those above are also in the mix. For each of these gases we need to consider four factors that determine their long-term impact on global warming: the concentration; the global warming potential; the “lifetime” of the g...

42. EV: Short for Evil??

  EV: Short for Evil?? “Is Biden driving up gas prices to get you to buy an EV?” was a recently cited concern in an Associated Press release. It reported on a circulating rumor that, in a nimble feat of opportunism, the American President was possibly exploiting - or even encouraging - the Russian invasion of the Ukraine so we would switch to electric cars.  It seems it’s become fashionable to charge your political opponent with the exact bad thing you are likely to be charged with, either because you are planning to do it or because you did it and have no excuse. This sort of discourse has been effective with many voters. If that’s what’s going on here, might it follow that there’s an anti -EV conspiracy brewing right now? We recently came across a few Facebook article re-posts listing all the drawbacks of electric vehicles.  Around the same time we saw a New York Times article about the backlash against an electric truck manufacturer building a plant in Georgia.  ...

41. Is Carbon-Capture-and-Sequestration a Thing?

  Is Carbon-Capture-and-Sequestration a Thing? Carbon dioxide in the atmosphere is the primary driver of the “greenhouse effect,” that condition in which CO2 forms a nice blanket around the biosphere, keeping it warm enough for life to have evolved as it has. For a million years or so, atmospheric CO2 levels were relatively stable, fluctuating between 200 and 300 parts per million, and all life as we know it was maintained. Small human-caused  increases in CO2 began with agriculture, but the industrial revolution triggered an abrupt and profound rate of CO2 increase, from roughly 280 parts per million to around 420 today. In just over 200 years we have released the carbon from fossil plants and animals that took several hundred million years to form.   To prevent catastrophic warming, we need to stop emitting CO2. And since we didn’t start cutting back 20 or 30 years ago, we will likely also have to remove CO2 from the atmosphere. Even if the world achieves its net zero 2...

40. Miracle Electric Heaters

  Miracle Electric Heaters “This little, super-efficient electric heater ONLY uses 1525 watts of electricity, yet puts out a WHOPPING 5200 Btus of heat!!!”  What is wrong in this statement? A couple of things. One is just my pet peeve, confusing units of power and units of energy. It should read “5200 Btu per hour .” The ”watt” is a measure of power, or the rate at which you use energy, while the “Btu” is an amount of energy. It’s like the difference between speed and distance. If the Btu is the “distance” the watt is the “speed.” (Imagine you asked a car salesman how fast this car could go, and he told you it would go 600 km on a tank of gas.) But, it turns out that in the heating trade,  “Btu per hour,” is often shortened to just “Btu,” so OK. BUT: The second flaw in the statement is a deception. 1525 watts is equal to 5200 Btu/hour. 1525 W is the rate at which the heater uses electrical energy, and 5200 Btu/hour is the rate at which it puts out thermal energy. They are...