what doesn't match? I'm on EV1-A and it matches both rates and times on the tariff. I don't see any graphics for EV1-A
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Natural Gas vs Heat pumps for heating
- Thread starter wwhitney
- Start date
I added a heat pump water heater Stiebel Eltron - Accelera. Suppose to be the best. German company. Mine is a hybrid system. In the winter I have a boiler that heats my house - radiant heat. In the summer (spring - fall) I turn my boiler off and my heat pump water heater supplies all my dhw. In the winter I turn the temp way down and it preheats the water that goes into my indirect water heater that is heated by the boiler.
Here's a one stop shop that makes the argument we should all un-enroll from MCE's "deep green" or whatever they call their "all renewables" tier.
If you believe what this Bob Silvestri fellow is saying... this "community choice aggregator" doesn't do much other than to make generation costs even more expensive than what one would pay if they hit up PG&E directly. And that's crazy since PG&E = sucks. Literally all MCE is doing now is making it so its customers are deceived into thinking paying MCE is making the world a better place by allowing MCE to purchase more renewable credits instead of dirty credits. But as Wayne says... energy is energy. It's not like MCE is taking the premium to then become responsible for making more renewable sources.
While I think there are some valid points on both sides of the CCA argument, that article from August 2020 has not aged well - it cites plummeting natural gas and energy prices in the depths of the pandemic as one reason for MCE's hidden losses. Meanwhile, articles from this past week predict natural gas prices will be through the roof this winter. Also, the article is mainly complaining about MCE specifically, including their high salaries, and points out the Monterey Bay CCA as being one that is better managed with low costs.
But I do feel in general the CCA approach is a somewhat flawed market approach unless the retail, generation, and distribution are fully decoupled, esp by legally separating and regulating PG&E's distribution monopoly apart from retail and generation businesses. (But still need some regulations on retail and generation markets so we don't end up with market manipulation per Enron, nor with a Texas-sized debacle during environmental crises...)
While I don't know the details about how MCE is running their CCA compared to others like SVCE (Santa Clara County) and PCE (San Mateo County), I have read other stories that show that many CCAs have been taking real actions to procure renewable energy with power purchase agreements that make renewable projects possible. Some of these contracts also include storage so that the power can be drawn during Peak hours when demand is higher and power purchase would otherwise be higher.
You are completely wrong. Even if the grid was 100% powered by NG, the amount of NG required to generate electricity to heat water with electric heat pumps is still a lot less than heating the water directly from NG in the home. And since the grid is largely made up of renewables and increasing every year, it's far FAR less carbon than using NG directly.
You're statement is wrong on so many levels and is the kind of ignorance used to drive bad policy making and the kind of ignorance that might already result in us having gone past the point of no return on run away greenhouse headed towards Venus.
You don't need solar to be more economic than NG. Heating water is the same cost with electric as it is with NG as long as you use a heat pump water heater. Same with heating the home.
I did not realize that. I know that driving and EV charged from an NG power plant is more efficient than driving an NG vehicle because the ICE is so inefficient, but I figured that heating a tank of water with an NG flame would be more efficient than using the flame to create steam to make electricity and then using that electricity (after some transmission loss) to heat water in the home. But perhaps the heat pump is a lot more efficient because it captures environmental heat.
It's the same with EVs. It's more efficient to charge and drive electric cars with electricity made NG or gasoline fired plants than burning the gasoline directly. The efficiency is dramatically higher at scale. But the main thing is that if you pick the device at the leafs(homes and such) that use the grid instead of burning carbon directly, as the grid is cleaned up, so are your electric appliances. Recent improvements in heat pump efficiency and reliability make it a no brainer.
Completely wrong? have you done that calc for NG heating water vs NG producing electricity and than using heat pump water heater? Sure would like to see it
I did some spot checks today on % CAISO grid on NG
3pm 36% NG
6:30pm 48% NG
Without a very very large amount of storage, we cannot live without a good portion of NG creating electricity for quite some time.
Check out the efficiencies of modern gas furnaces. I bet you would be surprised. Then do a compare of NG burn to produce electricity and heat house with heat pump.
Modern heat pump water heaters have a UEF of 4x. Do your research.
do yours
A modern gas furnace converts 94% of fuel into heat.
A NG plant at best converts 45% of fuel into Electricity. Then we have to have efficiency of the Heat pump. Its not even close for heating a home
Look, I have 12 KW of solar panels and 3 PWs. I was a nuclear engineer and was into solar and "soft energy paths" as it was called then in the late 70s. Fact is that we cannot do without NG for a long time. Too bad PG&E is decommissioning Diablo. That is a steady 10% baseline of power.
Tell me how much Storage do you need for the grid to be stable with 100% renewable. Can you do that math?
94% and 45% sound about right. Let's subtract 10% for transmission losses. So breakeven occurs when the heat pump COP is 2.4 or higher. Which for a modern heat pump is true for much/most of the heating season in much/most of the US.
Similar math should apply, as the standby losses for a heat pump tank and a NG tank should be comparable. If it's only an 80% efficient NG tank water heater, then the breakeven COP is now only 2.0. Of course, you have to look at where that heat is coming from.
Short answer is that electrification with heat pumps is probably around break even carbon-wise for 100% NG-fueled electricity, and a carbon win in locations with a lower carbon grid.
Cheers, Wayne
not sure I get your math
I don't see a carbon win until we have close to 100% renewable for home heating
A heat pump can move more heat than the equivalent of the electrical energy put in. So the "efficiency" or COP is typically above 1. [When it falls below one, you're better off using electrical resistance heating.] Depending on the details of construction and the temperature differential, the COP can be anywhere from 1 to, say, 6.
So if 40% of the NG heat energy gets turned into on-site electricity, and that electricity is used in a heat pump with a COP of 2.4, then it moves heat equal to 96% of the heat energy of the NG. Comparable to directly burning it on-site and capturing 94% of the heat energy of the NG. The comparison assumes that losses in moving the NG to the house vs to the power plant are equal.
Cheers, Wayne
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