Primary energy vs final energy: why replacing fossil fuels may not be so hard
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Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#2The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about.
“Electrical devices can sometimes offer higher than 100% efficiency,” said BNEF analyst Matthias Kimmel. That might seem odd. How can there be more energy as output than input? But that’s exactly what heat pumps and air conditioners do. They use electricity to shift heat from the outside to inside, or vice-versa, and typically provide three units of energy service for one unit of energy input, meaning an efficiency of 300%.Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#3The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
That was easy. Just put a few of them back-to-back and you'll have 10X as much energy.
Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#4The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
I wrote the story. The efficiency here isn't breaking the first law of thermodynamics. It's just the industry's way of measuring how much work gets done for a certain amount of input. If the work is heating or cooling, then shifting heat from in one direction or another can be done using heat pumps, which move three units of thermal energy for every unit of electrical energy consumed. Might that explain the conundrum?
Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#5The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
Air conditioners move heat from inside the house to outside. So, they can provide more cooling (move more heat) than the equivalent input energy. That is how you come up with greater than 100% efficiency.
Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#6The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
What is wrong with the concept of a heat pump? A resistor converts electricity into heat 100% efficiently, and a heat pump is often 3x as efficient at heating a house vs electric baseboards.
Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#7The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
Heat pumps move more heat (which has the same unit as energy, that's why you can put the numbers in a ratio and get a unitless number) than they use energy for the process. This is the crucial point for heating with them, otherwise they would make little sense (except for using them for cooling) over having an electric heater instead.
Here is something to read on this:
https://en.wikipedia.org/wiki/Coefficient_of_performance
Jump to "Examples" if you like concrete examples.
Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#8The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
I wrote the story. The efficiency here isn't breaking the first law of thermodynamics. It's just the industry's way of measuring how much work gets done for a certain amount of input. If the work is heating or cooling, then shifting heat from in one direction or another can be done using heat pumps, which move three units of thermal energy for every unit of electrical energy consumed. Might that explain the conundrum…
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Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#9The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
That was easy. Just put a few of them back-to-back and you'll have 10X as much energy.
Because this doesn't violate the second law of thermodynamics it is impossible to get to 10X - https://en.wikipedia.org/wiki/Coefficient_of_performance
Re: Primary energy vs final energy: why replacing fossil fuels may not be so hard
#10The article tries to explain the difference between primary, final and useful energy to justify why moving to renewables would be easier than at first glance. But I just don't feel like I got convinced in the end. If anything I'm more confused now than before. In special this part about air conditioners being 300% efficient sounds to me like maybe they don't know what they are talking about. “Electrical devices can s…
What is wrong with the concept of a heat pump? A resistor converts electricity into heat 100% efficiently, and a heat pump is often 3x as efficient at heating a house vs electric baseboards.
Ok then the electric baseboard is 30% efficient vs the heatpump which is 100% efficient.