Carbon Wars: The New EPA Rules to Reduce Carbon Emissions at U.S. Power Plants

[Jeff Miller]

Correct, but they are not just tightly ring-fencing coal and natural gas. The renewables, apart from hydro are part of this mix, to encourage rotation into them. So, going to wind or solar panels is ok, but not nuclear, since the vast majority (94%) of its MWh are deducted from the rate-based denominator. I followed up on page 41, of 645, and note EPA intends to keep control of the "state specific rate-based goal set by the EPA". So, not sure state plans even get the option of adding nuclear back. Comments are the only means, it seems.

Yes, they say all kinds of pleasant things, but in the end, do you agree they took 94% out? EIA has TWH data, for reference. It's pretty easy to tell EPA's TWH values are very short.

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 how each state can achieve their goal.

1. How the EPA comes up with the goal.

In a nutshell, I think they do this:

a) add up all the CO2 emissions in pounds from the electrical sector in each state
b) add up all fossil fuel generated electrical energy from the state
c) take the ratio of a) to b)

That's the starting point.

They then do the following calculation to determine what each state's goal should be.

a) assume that the existing coal plants in the state are made ~5% more efficient (reduces the numerator)
b) assume that existing natural gas combined cycle plants are used at a much higher rate (~70%) than they are now in lieu of coal (reduces the numerator)
c) assume that the 6% of nukes that the EPA figures are due to be retired are not retired. Assume the 5 new nukes that are being built now are finished. Both these energy generation terms are added to the denominator. Assume that new renewables - wind and solar - are built each each from 2020 to 2030 at a rate which the EPA thinks is feasible and add the energy generated from these to the denominator.
d) assume the state implements an energy efficiency program and add the cumulative energy savings (1.5% per year) to the denominator.

The ratio calculated in this way is the goal expressed in terms of CO2 intensity - lbs/MWH.

The state then has a choice of trying to meet the intensity (lbs/MWH) goal, or the equivalent goal of a fixed emission in pounds.

2. How the state achieves its goal. The document repeatedly emphasizes that the EPA is not dictating to the states how they should meet the goal. All they care about is that the state has a credible, enforceable plan which meets the goal. So if a state comes back and says they are going to meet their goal by in part building new nukes, the EPA would be fine with that. They say this very explicitly on page 39:

"States may also identify technologies or strategies that are not explicitly mentioned in any of the four building blocks [basically points a,b,c,d above] and may use those technologies or strategies as part of their overall plans (e.g., market based trading programs or construction of new natural [gas] combined cycle units or nuclear plants).

The concern here, is carbon dioxide. If you are the Carolina's, not looking at wind, finding the $2 solar costs these other guys are using (presumably w/o land costs) too expensive, not able to tap hydro, etc., you actually have an incentive to stay within the calculation fence, and use natural gas. So long as you have some coal, its bound to help and would come at cheapest cost. But it increases CO2.

Yes. The EPA document says that in 2030 they still expect more than 30% of the total electrical generation will come from coal and more than 30% from gas. That is to say, the EPA's goal is extremely unambitious. Maybe it's all they can do politically, but objectively it is weak.

Lines were drawn deep in the nuclear / environmental debate long ago. The staffs of those drawing policy like this have old axes to grind. Young ones don't want new enemies. In the analysis above, the 3.2 trillion for solar, again without paying for 5,000 square miles of land, could be beat by the 2.3 trillion that scaling up the 15bb/2.2GW GA plants would yield. I'm not here to say nuclear is safe, but it is a debate over the extra decade, or so, we could buy before reaching whatever the 1,000Gt target might do. The conclusions on that figure are fluid, but things like water vapor feedbacks, etc. need more time before we know what wrenches they will throw us.

Indeed. I believe a serious plan would pull out all the stops and have us build not just enough nukes to satisfy our current electrical needs (400 more nukes), but also enough to satisfy the bulk of our transport and heating needs. I'd do this in conjunction with aggressive energy efficiency and renewable programs. Economies of scale would drive construction costs way down. Implemented world wide, such a plan largely solve our energy and carbon problems.

 

[Jeff Miller]

Y
Solar PV is like a rising tide... at its projected cost point its hard not to see distributed generation overtaking everything. $2/w is today... $1/w in 2020... the primary ingredients in a solar panel, Si and Al are literally the most common materials on the planet so there aren't a lot of resource bottlenecks. Might as well back the winning side now...

Are there problems with solar PV? Of course, but we have a few years before we need to solve them. We currently generate 0.41% of electricity from solar. At ~16% we'll need a robust demand response program EVs can help with that. There does't appear to be a lot of information on how much can be generated with Solar PV before storage is NEEDED but its >20%...

http://cleantechnica.com/2013/07/12/sunday-solar-sunday-germany-solar-power-record-in-depth/

What is your take on this?

Renewable Unreliability and German Energy | The Energy Collective

 

[nwdiver]

What is your take on this?

Renewable Unreliability and German Energy | The Energy Collective

My take on that is ~20% appears to be the point that storage / demand response needs to take a more prominent role. The US is no where near those levels... Solar PV will be the cheapest SOURCE of electricity (already is in some areas)... our efforts should be geared toward finding effective ways to use that power when it's available and storing it; not the construction of new thermal power plants that will become stranded capital before they've paid for themselves.

Another consideration is the relatively small size of Germany (smaller than Texas)... Solar integration is easier without storage or demand response in a country the spans multiple time zones since excess power can be transmitted west in the mornings and back east in the evenings.

 

[Robert.Boston]

Germany is part of a strongly interconnected grid; it can import power from France, Norway, etc. if its solar output is low, or export power if it has surplus.

Texas is very weakly interconnected to the rest of the North American grid; it must stand on its own. (Imagine the chart below where the export/import entries were forced to be zero.)

The article sited by Jeff Miller is well written and reaches what, to me, is an unsurprising conclusion: as any particular resource becomes more abundant, its value declines. In modern electricity markets (such as in Germany and much of the US), the price paid by the system operator to generators is set by the incremental cost to serve load at that location (the "Locational Marginal Price" or LMP). Wind and solar always bid zero (or a small negative number), so any (positive) price is set by a nearby fossil-fired plant, which will be offering its power at a price high enough to cover its fuel and other variable costs.

As one chart in the report shows, the very high solar output is pushing high-cost fossil units offline (or to their minimum generation point), which means that some other, lower-cost unit is now setting the LMP paid to all generators, be they wind, solar, or fossil.

[Legend: yellow=solar, sage-green=wind, brown=fossil, light-green=exports, dark-green=imports, dark-blue line=day-ahead LMP, light-blue line=intraday LMP]

The really high LMPs will be during those periods (like Thursday evening in the chart above) where fossil output is high, implying that the system operator had to turn on some very pricey generators to meet load. Worse yet, because the solar output was so high, it may be the case that the system operator left some lower-cost but slow-ramping generators offline, so now the system is relying more heavily on high-cost, low-efficiency peaking units to match supply and demand.

This price effect is already very visible in other markets. Take a look at hydro in the Pacific Northwest, for example. During the snow melt in the spring, power prices plummet as all the dams have to operate at high capacity factors (there's not enough reservoir storage), so hydro resources have a lower average annual revenue/MWh than a gas-fired plant in the same area. Likewise, in Texas we see that prices are low on windy days.

I wasn't sure what the policy implication of the paper was, however. In my experience, all new (grid-scale) generators will have a long-term power purchase agreement. Without one, no bank would finance the project. Presumably these contracts prices reflect buyer's expectations of the generator's earned LMPs--but as someone who has prepared many reports for lenders to generation projects, we already included these price effects in our forecasts.

I agree with @nwdiver's note, though, that solar up to 20% or so shouldn't cause problems. So, we've got a long way to go before I'll credit any arguments about bulk-system reliability issues caused by high distributed generation rates. This 20% figure is consistent with research my team did for the Southwest Power Pool a few years ago.

 

[Jeff Miller]

... our efforts should be geared toward finding effective ways to use that power when it's available and storing it; not the construction of new thermal power plants that will become stranded capital before they've paid for themselves.

Another consideration is the relatively small size of Germany (smaller than Texas)... Solar integration is easier without storage or demand response in a country the spans multiple time zones since excess power can be transmitted west in the mornings and back east in the evenings.

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 the benefits of diversification, not to mention there is no solar produced at night which starts around 4pm in the winter in Chicago.

The larger point, with which you seem to agree, is that we currently do not have widely available, effective ways of storing intermittent power in large scale (hydro but only in certain select locations). Without cost effective and efficient storage, I don't see how wind and solar will ever be able to replace more than a fraction of fossil fuels we currently burn every day, not just to produce electricity, but to heat our homes and fly our planes and produce all the stuff we consume. You and I both agree that we need to drastically global carbon emissions in the next few decades, but where I don't follow you is in how, without economical storage, solar can be more than a very partial and incomplete solution - even if it were literally free. By all means, we should continue to develop solar and wind resources and put serious money into research on storage. But should we put all our climate eggs in this basket, counting on a breakthrough in storage costs and technology in the next few decades, something which is far from assured?

Here's something I think about a lot. In January and February of this year I used over 20 therms of energy from natural gas each day to heat my 100 year old brick house. Expressed in kwh, that is about 600 kwh per day, or about 25x the amount of electricity we use each day, including charging the car. My boiler is pretty efficient, so most of this energy is actually going to heat the house rather than up the chimney. To go carbon free, I can't be burning gas to heat my house. So what are my options? Efficiency is one. I've already done a fair amount on that front and hope to do more, but the reality is that it is basically impossible to make an old, brick house super energy efficient (if there is a way, I'd love to hear about it). A heat exchanger is another. One of my neighbors just installed a geothermal system. It cost him 60k, or 42k after the tax rebate. He told me with this system, he saved 25% on his heating costs this winter. Given the expenditure, that is somewhat underwhelming. (In the summer, he saves ~80% in cooling costs, which is much better, but cooling in the north uses far less energy than heating). I've also looked into air heat pumps. Everyone I spoke to said that in our climate, a) even the super efficient ones won't heat the house in winter, and b) you'd never recover your investment. I suppose I could do it anyway, but unless something is economical, it won't be widely adopted, so I don't see this as really a viable solution.

Let's say that by some miracle, I can get my heating requirements down by 1/3, to 400kwh per day (I am extremely doubtful that this is attainable, short of tearing the house down and rebuilding, but let's assume it anyway). If I'm not burning fossil fuels, where is that 400 kwh of thermal energy going to come from? Assuming 3.5 hours of peak sun equivalent a day in the winter (which is wildly optimistic - 3.5 is average throughout the entire year in Chicago), I'd need a 110kw solar system. But I'd need much more than that, because there are weeks when you don't see the sun at all. But let's just stick with 110kw. Even at $2 a watt (which is half the price I have been quoted for a 10kw system), that is 220k, or around 150k after rebates. And that is before storage. I could buy five 85 kwh batteries from Tesla at 10k a pop (or whatever they cost, if they were selling them, which I don't think they are) and that would give me enough storage to heat my house for one day (assuming again that I can achieve dramatic gains in conservation). So I could easily spend 200k and still not have a viable system to even heat my house in winter. And this is just one part of the energy I use each day. I don't see the numbers adding up for solar and wind being the complete solution to our energy needs, even assuming we had modern, continent spanning, smart grid, which we don't.

 

[nwdiver]

Getting to 100% renewables can roughly be viewed like this;

Stage 1: <20% - REALLY EASY
Stage 2: 20-50% - Demand Response / Thermal Storage (2x as hard as Stage 1)
Stage 3: 50-80% - Moderate Storage (2x as hard as Stage 2)
Stage 4: 80-95% - Significant Storage (2x as hard as Stage 3)
Stage 5: 95-100% - Conversion of electricity to H2 or hydrocarbons (2x as hard as Stage 4)

I don't see this as something that needs to be "planned" but for lack of a better word, it will probably sort itself out organically. "Net Metering" will gradually go out of favor and solar PV owners will get next to nothing for exports (this is already happening in some areas) this creates an incentive for storage.

You must think of these steps in terms of WHEN they would be tackled... the challenges increase exponentially as you increase the penetration of renewables but the costs also depreciate over time as the technology gets cheaper... so in ~20 years "Stage 5" might be the same cost as "Stage 1" is today. 1MWh of grid storage is a fraction the cost today as it was 10 years ago. This is the main thing that makes me so pessimistic about the chances of nuclear power... it's costs have only been rising.

600kWhs is A LOT but you should be able to knock that down with better insulation. I dense packed cellulose in my walls and added ~18" to my attic, that reduced my energy loses by ~50%. Geothermal is best but also cost prohibitive for most people, some of the new air source heat pumps like the Mitsubishi Hyper Heat work into the negative teens. For winter energy storage PCMs (Phase Change Materials) will likely play a more significant role than batteries. I recently discovered Sodium Acetate that's used for "rechargeable" heat pack... somehow I've never come across it before... When heated to 130F it liquifies and will remain as a liquid when cooled until disturbed then it will rapidly "freeze" resulting in an exothermic reaction that gives off ~77Wh/kg. You can buy it in bulk for ~$1.30/kg. So for ~$1100 you can store more thermal energy than is in a Tesla battery pack.

https://www.youtube.com/watch?v=ce-mM7R11Lo
https://www.youtube.com/watch?v=nAct0ZSjDZQ

 

[David_Cary]

Totally OT of course, but you probably need to build new walls inside the house - you don't need to tear down the brick structure.

Maybe you should consider the payback on doing that. Might be less than 50 years.

I've often wondered if it makes environmental sense to abandon the old houses in the Midwest (and other cold areas). Throw in the less than ideal solar exposure and the fact that a/c is the easiest to make go away with solar. And then add in EVs decreased efficiency in the cold.

The answer to AGW is of course suicide but most people would lessen their impact if they just moved out of the North. Getting to zero carbon for transportation and housing is not terribly hard in the South. But even here, solar can't keep up with heating the house.

 

[Jeff Miller]

Getting to 100% renewables can roughly be viewed like this;

Stage 1: <20% - REALLY EASY
Stage 2: 20-50% - Demand Response / Thermal Storage (2x as hard as Stage 1)
Stage 3: 50-80% - Moderate Storage (2x as hard as Stage 2)
Stage 4: 80-95% - Significant Storage (2x as hard as Stage 3)
Stage 5: 95-100% - Conversion of electricity to H2 or hydrocarbons (2x as hard as Stage 4)

I don't see this as something that needs to be "planned" but for lack of a better word, it will probably sort itself out organically. "Net Metering" will gradually go out of favor and solar PV owners will get next to nothing for exports (this is already happening in some areas) this creates an incentive for storage.

You must think of these steps in terms of WHEN they would be tackled... the challenges increase exponentially as you increase the penetration of renewables but the costs also depreciate over time as the technology gets cheaper... so in ~20 years "Stage 5" might be the same cost as "Stage 1" is today. 1MWh of grid storage is a fraction the cost today as it was 10 years ago. This is the main thing that makes me so pessimistic about the chances of nuclear power... it's costs have only been rising.

600kWhs is A LOT but you should be able to knock that down with better insulation. I dense packed cellulose in my walls and added ~18" to my attic, that reduced my energy loses by ~50%. Geothermal is best but also cost prohibitive for most people, some of the new air source heat pumps like the Mitsubishi Hyper Heat work into the negative teens. For winter energy storage PCMs (Phase Change Materials) will likely play a more significant role than batteries. I recently discovered Sodium Acetate that's used for "rechargeable" heat pack... somehow I've never come across it before... When heated to 130F it liquifies and will remain as a liquid when cooled until disturbed then it will rapidly "freeze" resulting in an exothermic reaction that gives off ~77Wh/kg. You can buy it in bulk for ~$1.30/kg. So for ~$1100 you can store more thermal energy than is in a Tesla battery pack.

https://www.youtube.com/watch?v=ce-mM7R11Lo
https://www.youtube.com/watch?v=nAct0ZSjDZQ

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 build, but it has the advantage that it is a solution. It will work. We could do it if we wanted to - there are no technical obstacles. It's a matter of having the political will. Expensive, but on a per year basis comparable to what we've wasted in fruitless wars over the last decade. I am also firmly persuaded that costs would come down as we scaled up production. We could build small modular nukes at all the old coal plants. The transmission infrastructure is already there. China has built dozens of nukes in the last decade or so and are building dozens more now. As far as I can tell, these are mostly on time and on budget and cost (if I recall) a third of what we are spending. Obviously some of this is the cost of labor, but a lot is probably from economies of scale. This is unrelated, but a massive public works project like this (no longer fashionable I know) could create lots of high skill jobs for the younger generation many of whom are now underemployed. As is stands, we risk losing leadership in nuclear technology to China, which is building a bunch of advanced experimental reactors of different designs, many of which were first developed or proposed here. Some of these are likely to become the new standards.

I agree that 600 kwh house is a lot, but it's definitely in the ball park - to within maybe a factor of two or three? - of what most homeowners with older houses use around here. The problem with insulation in these brick houses is that you only have about an inch between the lathe and the bricks. In the rooms I've remodeled I put in 1" foam board which does something, but it's far from optimal. I intend to insulate the attic but am a bit worried about moisture. I'll check out the Sodium Acetate.

- - - Updated - - -

Totally OT of course, but you probably need to build new walls inside the house - you don't need to tear down the brick structure.

Maybe you should consider the payback on doing that. Might be less than 50 years.

I've often wondered if it makes environmental sense to abandon the old houses in the Midwest (and other cold areas). Throw in the less than ideal solar exposure and the fact that a/c is the easiest to make go away with solar. And then add in EVs decreased efficiency in the cold.

The answer to AGW is of course suicide but most people would lessen their impact if they just moved out of the North. Getting to zero carbon for transportation and housing is not terribly hard in the South. But even here, solar can't keep up with heating the house.

I've thought about that as well, but it would be a huge project and the payback might indeed be 50 years if ever. I've also thought about whether abandoning old houses makes sense. The problem is the the wealth/mortgages tied up in these structures is huge and also accounts for the majority of a typical person's net worth. Abandoning them would make the collapse of the housing bubble look like walk in the park. Going forward, it is possible to make carbon neutral houses up here, but it will take a long time to cycle through the existing housing and commercial stock. In the meanwhile, building lots of nuclear plants to power them seems somewhat preferable to collective suicide.

 

[CalDreamin]

According to the latest data from the EIA, solar PV generated 9,655 GWh from Apr13 to Mar14, and solar thermal, 1,119 GWh, for a total of 10,774 GWh. All renewable sources (including solar) were 526,768 GWh, of which conventional hydro was 51% and wind was 33%. Total generation in the US for that period was 4,107,259 GWh: 40% coal, 27% nat gas, 19% nuclear, 6% hydro, 6% other renewable. Solar's overall contribution was 10,774/4,107,259 = 0.2%.

I was curious how utility-scale solar could have supplied 6.2% of California's grid recently, while supplying only 0.2% of the U.S. grid for the 12 months ending in March 2014. Part of the reason is that a day in June will produce more solar than an average day.

Another factor is the time scale of looking at a recent day vs. an annual total. Utility-scale solar is growing rapidly in California, with utility-scale PV generation almost tripling over the last year.

But the key explanation is that most of the utility-scale solar generation in the U.S. is in California.

Utility-scale solar generation for the month of February 2014
U.S. per the EIA: Solar PV = 775 GWh, Solar thermal = 83 GWh, Total Solar = 858 GWh
California per the CAISO: Solar PV = 566 GWh, Solar thermal = 24 GWh, Total Solar = 590 GWh

In February, California had 590/858 = 69% of the total U.S. utility-scale solar generation. I did not realize that the U.S. utility-scale solar is so heavily concentrated in California.

Another 4.8 GW of utility-scale solar generation capacity is already approved by California to go online over the next several years, which would more than double utility-scale solar in the state. Solar is 83% of the state's approved future Renewable Portfolio Standard projects now under development. The RPS mandates that by 2020, 33% of California's electric power be from RPS eligible renewables.

Since California utilities can satisfy the RPS mandate with solar PV, solar thermal, geothermal, wind, biomass, biogas, or small hydro generation, the fact that solar is a large majority of RPS projects under development indicates to me that solar is now less expensive to build than other renewable options, even compared to wind.

But because utility-scale solar seems to be largely concentrated in California where there is an RPS mandate and not other U.S. states that have also have great solar potential suggests to me that utility-scale solar might not be cost competitive yet with fossil fuel generation.

 

[stopcrazypp]

Nuclear is expensive to build, but it has the advantage that it is a solution. It will work. We could do it if we wanted to - there are no technical obstacles. It's a matter of having the political will.

Nuclear isn't immune to the time issue either. It also takes a long time to get nukes online in the US esp. when you go through all the regulatory paperwork (and perhaps opposition by the local public). China has cheap nuclear plants, but that's driven primarily by low labor costs (that simply can't be matched by other nations). China also has a more lax regulatory and legal structure (plus they don't have to care about public opposition) which helps reduce the time required.

I think nwdiver's argument is that getting to 20% renewables is going to be less expensive and cheaper than trying to go a nuclear route and can be accomplish in similar or better time frames. Plus although nuclear would address the CO2 issue, it doesn't really address the sustainability issue (we still have limited uranium/thorium supplies which will last a similar projected time frame as fossil fuels).

The EIA cost estimates seems to show utility scale solar and wind is rapidly decreasing in costs (hydro is also decreasing), nuclear holding about the same. On the fossil fuel side, Coal is rising in costs, NG is reducing costs. So it seems a strategy of reducing coal and increasing renewables and NG (perhaps with CCS) is going to be the way forward.
http://www.eia.gov/forecasts/capitalcost/

 

[Robert.Boston]

I've often wondered if it makes environmental sense to abandon the old houses in the Midwest (and other cold areas). Throw in the less than ideal solar exposure and the fact that a/c is the easiest to make go away with solar. And then add in EVs decreased efficiency in the cold.

An old friend of mine was a professor of dentistry. He and some of his Harvard colleagues were hired by the Army to develop the most cost-effective plan for soldiers' dental care. Their report concluded that this was to extract all the teeth from new recruits and issue dentures, thereby eliminating all expensive surgeries.

Sometimes doing the most cost-effective thing ignores intangibles, like the beauty of an old neighborhood with graceful, albeit poorly insulated homes. It would be great to see tougher building codes to ensure that all the new homes are sensibly insulated, etc. But a scorched-earth policy on old homes? Too far, IMO.

 

[Jeff Miller]

Nuclear isn't immune to the time issue either. It also takes a long time to get nukes online in the US esp. when you go through all the regulatory paperwork (and perhaps opposition by the local public). China has cheap nuclear plants, but that's driven primarily by low labor costs (that simply can't be matched by other nations). China also has a more lax regulatory and legal structure (plus they don't have to care about public opposition) which helps reduce the time required.

I think nwdiver's argument is that getting to 20% renewables is going to be less expensive and cheaper than trying to go a nuclear route and can be accomplish in similar or better time frames. Plus although nuclear would address the CO2 issue, it doesn't really address the sustainability issue (we still have limited uranium/thorium supplies which will last a similar projected time frame as fossil fuels).

The EIA cost estimates seems to show utility scale solar and wind is rapidly decreasing in costs (hydro is also decreasing), nuclear holding about the same. On the fossil fuel side, Coal is rising in costs, NG is reducing costs. So it seems a strategy of reducing coal and increasing renewables and NG (perhaps with CCS) is going to be the way forward.
http://www.eia.gov/forecasts/capitalcost/

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 proposed reactors. Labor costs will be higher here, but if we had a vibrant rather than moribund nuclear industry, competition and economies of scale would drive costs down. I agree that the biggest hurdle is public opinion. The Sierra Club and other groups have spent decades terrifying the public with tales of cataclysmic nuclear meltdowns, nuclear waste, and proliferation so a large part of the public isn't willing to do a hard cost benefit analysis. So a big part of the job will be in educating the public and giving them the information required to make objective decisions. That requires political leadership, which is sorely lacking.

I agree with nwdiver's 20% but I don't see what happens after that. Maybe we'll have solved the storage problem, maybe not. I'd rather not take that gamble.

The most promising Gen IV reactors are breeder reactors. These have numerous advantages to 1950s design thermal reactors on which all operating commercial reactors are based. Breeders burn almost all the fuel, rather than a tiny fraction of it. They also burn almost all the wastes, and what remains has a half life of hundreds of years rather than thousands. Much less mining would be required (not much is required now, compared to coal and fracking). These reactors are designed to be passively safe. If the power goes out, the reactor shuts itself down. The fuel in some designs cannot be easily used to make a bomb. Finally because they are breeders, you can create new fuel from non-fissile material like throium. This would supply enough energy to last last tens of millions of years at current rates, with extremely small amounts of not so dangerous waste.

 

[nwdiver]

I work in the nuclear fuel supply chain... fuel won't be an issue for another few centuries... we've got ~400,000 tons of depleted Uranium sitting in Paducah. Depleted Uranium usually still has ~0.2% U235 vs ~0.7% U235 in natural ore.

The AP1000 has a passive shutdown system... safety isn't a problem.

But... an AP1000 costs ~$7B and that cost is VERY unlikely to fall <$5B even at scale.

The problem with thermal plants is the expense of converting heat to electricity.

A Solar PV module is more than capable of happily converting sunlight to DC power for 60+ years with ZERO maintenance degrading <30% in that time.
http://www.us.schott.com/photovolta...ute-long-term-study-schott-solar-26-years.pdf

We've been waiting for a nuclear renaissance for ~30 years and where has it gotten us? In that time the cost of Solar PV has plummeted by nearly 99% while the cost of nuclear power has risen ~400%.

When we retire "net metering" and DG customers are "giving" power to their local utility when they can't store or self-consume it they WILL adopt solutions... we have them... well the Germans do. Sprechen Sie Deutch?

https://www.youtube.com/watch?v=ecPsL2g9Nbw

 

[Dave EV]

Here's something I think about a lot. In January and February of this year I used over 20 therms of energy from natural gas each day to heat my 100 year old brick house. Expressed in kwh, that is about 600 kwh per day, or about 25x the amount of electricity we use each day, including charging the car. My boiler is pretty efficient, so most of this energy is actually going to heat the house rather than up the chimney. To go carbon free, I can't be burning gas to heat my house. So what are my options? Efficiency is one. I've already done a fair amount on that front and hope to do more, but the reality is that it is basically impossible to make an old, brick house super energy efficient (if there is a way, I'd love to hear about it)

Oh my, 20 therms/day is insane! How big is your house? There has to be a lot of low hanging fruit there in terms of efficiency.

 

[David_Cary]

The other issue of course is that 20 therms of NG can be replaced with far less than 600 kwh per day with the right technology. 20 therms a day is not uncommon for a large older house in the midwest. At $1 a therm, it probably represents on an annual basis less than 10% of their property tax.

The first easy fix is that electricity rates are higher than logical in much of the North. If your utility gave you heat pump rates and installed a good heat pump, you should be able to save 1/2 your heating bill - even compared to cheap NG.

I have to laugh about the intangibles. I can certainly appreciate the beauty of an old neighborhood but do I think it is worth the carbon waste - no. As far as living in the North in general, the population has spoken.

I used 150 therms last year for 5000 sqft. Chicago probably has 2x the HDDs that we have. What is that like 90% more efficient? Owning a Tesla while living in an old house in the North is a bit of pissing into the (personal carbon) wind.

 

[Jeff Miller]

Oh my, 20 therms/day is insane! How big is your house? There has to be a lot of low hanging fruit there in terms of efficiency.

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 smaller house built at the same time used 15% gas than we did this winter - pretty much exactly in line with the size difference of our houses. So I don't think my house is at all unusual among houses from that era. We both keep the thermostat around 65 so its not like we're going crazy wit the heat. The problem is these houses were not designed to be energy efficient. In 1911 you had a coal boiler and didn't worry about carbon emissions...

 

[Jeff Miller]

The other issue of course is that 20 therms of NG can be replaced with far less than 600 kwh per day with the right technology. 20 therms a day is not uncommon for a large older house in the midwest. At $1 a therm, it probably represents on an annual basis less than 10% of their property tax.

The first easy fix is that electricity rates are higher than logical in much of the North. If your utility gave you heat pump rates and installed a good heat pump, you should be able to save 1/2 your heating bill - even compared to cheap NG.

I have to laugh about the intangibles. I can certainly appreciate the beauty of an old neighborhood but do I think it is worth the carbon waste - no. As far as living in the North in general, the population has spoken.

I used 150 therms last year for 5000 sqft. Chicago probably has 2x the HDDs that we have. What is that like 90% more efficient? Owning a Tesla while living in an old house in the North is a bit of pissing into the (personal carbon) wind.

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 adopted it won't do much good. In that regard, I could sell my house and build a passive, zero heating energy house, and that might allow me to feel personally virtuous, but that wouldn't do anything to lower total carbon emissions; instead of me, someone else would be living in the house (which is one of millions just like it) emitting just as much carbon. I don't see walking away from these houses and moving to the south as a particularly viable solution. This home heating issue is one of the reasons why I believe we need a reliable, high intensity source of carbon free power. Hydro will do in Quebec, but elsewhere we need to pursue nuclear; if not, we will be burning gas and coal for many decades to come, rapid development of solar notwithstanding.

 

[Dave EV]

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.

Yeah, about the same footprint as my house (no attic-space or basement), but climate here helps a lot - only used 16 therms in the coldest month this year (6-9 of that is for hot water) Insulation is very basic - R13 in the walls and R21 in the ceilings, double-pane windows and doors. My HVAC is a dual heat-pump/gas setup, but I only run the heat-pump in the mildest temps because of high electricity prices here. In the winter an extra 100-250 kWh of electricity is typical with the heat-pump. It is a new HVAC system only a couple years old, though - the old one managed to get us 70+ therms in a month - so this new system is way more efficient.

65F interior temps is definitely more than reasonable, you really do need to figure out where the heat is going. From a climate/CO2 perspective I'm not sure how much a heat-pump would help in your situation. Air source heat-pumps are so much better than they used to be (especially look at mini-split units) that I would find it very difficult to justify the additional expensive of a geo-thermal system unless you really need a lot of heating capacity (and it seems that you do).

 

[nwdiver]

Jeff,

How thick is the insulation in your attic?

 

[Jeff Miller]

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 are no moisture barriers and because the attic is not vented, I'd be asking for trouble with moisture. This report suggests seems to suggest you need to be careful:

BSI-043: Don't Be Dense—Cellulose and Dense-Pack Insulation Building Science Information

So I've held off on this, even though I guess it would save 10 or 20%, based on reports like this:

http://www.buildingscience.com/docu...aluation-two-advanced-weatherization-packages

The house in winter: