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The paper I linked to above claims (Figure 5, Panel A) that marginal emissions in New England are about twice as high as average emissions. This sort of makes sense given that the NPCC baseload is very low carbon - firing up gas plants to supply marginal demand, somewhat unusually for the US...

Agreed. There is an interesting recent paper which attempts to estimate the marginal carbon emissions from the current electrical generation mix by time of day (see the tables at the end of the paper) for each of the nine electricity markets. The data is from 2007-2009 so is a bit dated, but I...

If you look at the outliers on the plot of phx182flyer's data above, they are mostly observations that include more than one day of data. For example, the pink point at 110 miles and energy 65 kwh is an observation that covers six days of driving. It makes sense that this point is above most of...

I assume biofuel is mostly corn ethanol which, given that almost as much fossil energy is required to make it as you get out of it, shouldn't be counted as renewable. Total primary: http://www.eia.gov/totalenergy/data/monthly/pdf/sec1_7.pdf Just renewables...

That's interesting. Just as another data point, phx182flyer was kind enough to let me look at his charging data. As expected, I get the basically the same regression coefficients that he got when I repeated his single variable regression, total_wh_wall ~ a * miles +b with the same very high...

It would be much more than 20x as much, wouldn't it? Assuming a low cost of $200 per kWh, a 1500 kWh battery would cost $300k. With depreciation, renting it would surely cost at least 15% per year, or almost 4k per month, so 600x as much as the grid.

There are ways to save money - on the margins - as your photos indicate. It's when we move beyond the margins, and consider the problem of 100% decarboniztion of the energy system across the entire world within the next few decades, that things become more complicated and more expensive. Lunch...

We as a society - or an an international community - are going to have to answer that question. I suggested one way - using some of the proceeds of a carbon tax; I'm sure there are other ideas. Eliminating carbon emissions quickly won't be free and won't be painless. On the other hand it need...

Do you have a source for that? I wouldn't doubt that it's true, but I haven't seen this correlation pointed out before. I was fairly clear that the reforms would be rolled back as soon as the higher insurance bills started to hit...

I understand you are making an economic argument and not arguing against nuclear power in itself and your prognosis may well be right. I'm just trying to get a handle on the numbers. As a first approximation, it seems reasonable to consider the total societal cost of a proposed carbon solution...

Can we afford to wait 15 years for PV to be only 20% of the total electrical grid, with presumably most of the grid still dominated by fossil fuels? Assuming that storage costs do come down at 4% per year like you hope (far from certain), what will those storage costs be? What will the total...

A portion of the revenues from a carbon tax. (There is an interesting recent paper by Brookings that shows that a revenue neutral carbon tax, coupled with tax reform - lowering the tax on capital income, though for example lowering corporate tax rates - would increase economic growth...

This is indeed a big part of the problem. The nuclear industry or whatever you want to call it, is not particularly interested in moving beyond the old LWR designs toward Gen IV reactors. They are like GM in some ways - large, inefficient, unresponsive, and arguably in some ways corrupt - rather...

PV is not displacing nuclear - cheap gas is. For example, most of the 2.2Gw capacity lost from shutting down the San Onofre plant will come from gas: Californias Plan to Replace San Onofre Nuclear: Green Success or Natural Gas Giveaway? : Greentech Media Burning gas emits CO2. Lots of CO2. And...

Do you mean energy in general or the source of energy to power the electrical grid (which is only a fraction of the total)?

Glad to hear that. I guess my issue must be unrelated.

It's unfortunate that you are having this problem especially on your first supercharger trip. Have you used any non-superchargers along the way? Coincidentally, When I left for work yesterday, I noticed the same red ring when I went to unplug the car. The car had only partially charged. I'd...

This table shows that a with 350kw diesel generator, you burn about 25 gallons of diesel per hour when its running full tilt: Approximate Diesel Generator Fuel Consumption Chart which works out to an efficiency of 350/(25*38) = 36%. It has a similar efficiency at lower loads. I wonder if you...

I don't quite follow how you come up with a price of $2.50 - $4.15 per kwh of electricity using a diesel generator. I would expect that a diesel generator would be about 33% efficient. There are around 38 kwh of energy per gallon of diesel. So I'd expect you'd get around 13 kwh per gallon, which...

The real problem with solar in the north is that we just get a lot less sun. The southwest for example gets almost twice as much sun as the northeast: http://www.nrel.gov/gis/images/eere_pv/national_photovoltaic_2012-01.jpg so solar investments are twice as good there, relative to the...

These guys say that the electrolyte used in commercial Li-ion batteries freezes at -30C. I don't know what electrolyte Tesla uses but it's possible that at extreme temperatures, there could be a problem with the electrolyte freezing. Proceedings of the Symposium on Lithium Batteries - Google...

If the car is unplugged and in sleep mode, it won't heat the battery. It would only heat the battery if it needed to do so while charging.

Thanks paco! It would definitely interesting to see how the charging losses of the other plugins compare.

Wow- that's an incredible reduction! I like the idea of a separate thread on efficiency.

At least in old masonry structures like ours, there is no "inside" on the exterior walls of the house, like there is for example between the studs of a newer home. There are several layers of brick (3 in our case), furring on which to nail the lath + a thin air gap, and then the lath and...

There's only 3/4 of an inch of airspace between the brick (3 courses) and the lath so there's not much I can do for the walls unfortunately, other than building them out from the inside as David.Cary suggested, which would be a huge project that I'm not really excited about undertaking. I'll...

I don't think there is any. The attic is finished, with plastered walls and ceiling. The roof is spanish tile which is a further complication. I've spoken with contractors who deal with these old houses about blowing in cellulose, but I get conflicting information. Some say that because there...

I am looking into heat pumps and want to get some more information from my neighbor who installed a geothermal system. He said he only saved 25%, but I'd like to get a better handle on that. In general though, if a solution is not economical, it won't be widely adopted, and if it is not widely...

The footprint is 40'x40'. It's an American foursquare, built in 1911. We live in the first 2 floors. There is finished attic that we don't heat. Half the basement is heated. So it was a reasonably large house for its day, but is not really large by current standards. A neighbor with a slightly...

I agree that it is time consuming to build nuclear nowadays. But it doesn't have to be that way. France built most of it's fleet in 20 years, as did the US. We would need to settle to streamline regulations by for example settling on a single design and getting this approved once for all...

I agree that step 1 is pretty easy and also agree that steps 2-5 or some unforeseen variation will also sort itself out organically. Where I am unpersuaded is that this sorting out will occur in a sufficiently short time frame to prevent dramatic changes to the climate. Nuclear is expensive to...

A wider geographic grid can obviously help smooth out fluctuations in supply and demand and should be pursued, as should a smart grid, although this won't be cheap. That said, weather phenomena that affect solar and wind output can, and often do, occur over very wide areas which somewhat reduces...

What is your take on this? Renewable Unreliability and German Energy | The Energy Collective

After reading your remarks, I went back and looked more carefully at the EPA proposal. It is a long repetitive, somewhat confusing document, but I believe it boils down to the following. First, it's important to distinguish two things: how the EPA comes up with their goal for each state, and...

Thanks Efusco. It occurred to me that the easiest way to avoid the rounding errors I noted above is simply to keep track of energy use directly. So in future updates if people post their energy totals (some people already do, and it's obviously also in the screen shot), I'll record that and it...

May numbers. One thing I've noticed is that because of rounding errors in the reported wh/m numbers, there can be slight inaccuracies in my calculation of the monthly wh/m numbers for people who don't report these number separately. For the monthly plots, I calculate wh/m_monthly =...

I'm not an expert on the legislation, but I took a look at these pages after reading your remark and interpret what they are saying in the report on pages 214 and following a bit differently than you. First, I think that in the table you link to they eliminate nuclear and hydro because they...

There are also wind resource maps on the internet. Here is a map for a residential windmill, which assumes you put the thing 30m above ground: WINDExchange: Residential-Scale 30-Meter Wind Maps They also have state level maps: WINDExchange: Wind for Homeowners, Farmers, and Businesses For...

Unfortunately, I am inclined to agree with this. Many (though by no means all) people are focused on what they see directly front of them. They don't account for the enormous costs that are coming down the pike, for which they and their children and grandchildren will pay, one way or another -...

That's interesting. When I got my solar quote in the spring of 2013, the installer wasn't all that optimistic that I'd get the rebate if I applied. It's kind of depressing though. Assuming for simplicity that the entire budget is used for residential solar, it would cover only 1000 kw installed...

To add to FlasherZ's comments, Illinois's renewable rebate program, while attractive on paper, is far from guaranteed. The state allocates a grand total of 1.5 million dollars per year to fund their solar and wind rebate. This princely sum is intended to cover the rebate for all solar PV, all...

That's right. We need to put a price on carbon if we want to decarbonize the entire energy system (not just the current grid) in the next few decades. If we don't do that, coal, gas, and oil will with near certainly remain the top sources of energy for a very long time, the rapid growth of...

Nuclear plants in the US are extremely reliable. They are on almost all the time. They have a capacity factor of 90% which is higher than all other sources of power (by a lot): EIA - Electricity Data EIA - Electricity Data If you want lots of reliable, carbon free power, then you do build...

This video is very well done - I like the animation, but the claim made at minute 3:16, that 4.5 kwh of electricity is required to refine a gallon of gas, is evidently not correct: Where will we get ALL that electricity whan most cars are electric? - Page 4 Your second link is interesting. It...

Thanks Mario. The January numbers I used for the US were 30 year averages, 1970 - 2000 or something like that. I don't recall where I got the average Jan temperature for Estonia, maybe this website: Average Weather In January For Tallinn, Estonia - WeatherSpark Because this winter was unusually...

I think I agree with that. One thing that is interesting is that because the Model S is so heavy and so aerodynamic, rolling resistance accounts for a much bigger fraction of the total resistance than it does for your average car. At high speeds (75 mph) it equals half the wind drag, and at...

I think it means that. And the fact that the new fossil fuel electrical generating capacity the Chinese built in 2013, mostly coal, exceeded the wind capacity that they built in 2013 by a factor of 6 and exceeded the solar capacity they built in 2013 by a factor of 27, seems to confirm that they...

1. It's hard to answer this question definitively because there may be correlations between the car one chooses to buy and how aggressively one drives. That said, if you take the data at face value, the self reported average wh/m of the 60s are about 6% less than the 85s. See tables 4 and 5 and...

Thanks. That is consistent with what I have read elsewhere.

I agree that 130 would be an adequate sample size to pin the probability down to within +/- .1 assuming a random sample, but I also agree that the sample is likely to be somewhat biased (not random) for the reason you give. I personally would be surprised if even 20% of drivers had solar, but...