Ryan_G

iTrader: (8)

Oh this gave me a good laugh and made work a bit better for the moment. Thanks.

Scrappy Jack

iTrader: (2)

This assumes the "typical suburban" family is a dual income home with school age children. I don't know if that is accurate or not. I do know many of my peers are single-earner households with small children that do not spend the majority of a day outside the house. For them, in Florida, it is not uncommon to run the AC at 76 - 78F all the time.

For my household, we are DINKs but do have dogs that stay at home. In addition, we live in a swamp that has been poured over with concrete (Central Florida) so there's no way I am turning the AC completely off most days. If I did, I'd be walking in to a blast furnace at the end of the day.

However, we do have a programmable thermostat and have it scale up to about 80F around the time we leave the house and scale down to about 78F as we get home, then drop down to about 76F around bedtime.

I could probably let it get a little warmer during the day when we are gone but I am not sure of the best way to measure the cost-effectiveness of a couple of degrees.

mgeoffriau

iTrader: (7)

Returning home from a vacation (that is, a vacation longer than the maximum programmable interval on the thermostat).

With the wifi-enabled thermostat, you could turn your A/C or heat back on a few hours before your expected arrival.

With only a programmable thermostat, you couldn't.



But yeah, that's about the only relatively common scenario I can imagine. And while it's common in the sense that it's a familiar concept, for most people it's not common in the sense that you take lengthy vacations very frequently.

Joe Perez

iTrader: (8)

Yes, I grew up on the gulf coast of FL (charlotte county) so I can sympathize with this.

It's also been my experience that Florida is a state of many extremes, which limit its usefulness in broad generalizations concerning income, employment, energy use, likelihood of being eaten by a carnivorous reptile or carried aloft by flying cockroaches, etc. By the same token, I would not cite California in a generalization involving home values, vehicle aftermarket parts laws, seismic activity, or the consumer retail price of gasoline.


The most recent data I can find here is from 1998, but in that report, 77% of all married women in the US with children aged 6 to 17 worked outside of the home. Of married women with children aged under 6, that number drops to 62%. But that's still pretty huge. Between 62% and 77% of all households with children have a mother who works outside the home.

Obviously this data ignores households containing a married couple in which ONLY the woman works, however I'd posit that number is relatively small.

And of course I am assuming that in dual-earner households, both working members have at least partially-overlapping schedules. I can't find specific data here, however I'd assume that the number of jobs in the US which are 9-5 (or thereabouts) exceeds those jobs in fields such as hospital nursing and law-enforcement patrol wherein the work hours routinely fall outside of the "norm" by a factor of at least 20:1, and probably closer to 100:1.


But these numbers (62% and 77%) represent the baseline, which is to say the lowest percentage of households of any demographic group in which the home is likely to be unoccupied for at least part of the day. For single-parent households, DINK households, and bachelor households, that percentage is probably closer to 100% minus the unemployment rate.





On the morning of Sunday of Week 1, note the reading of your power meter. Do nothing to change your energy usage habits that week.

On the morning of Sunday of Week 2, note the reading of your power meter. Configure your programmable thermostat for optimum efficiency.

Repeat steps 1 and 2 for weeks 3 and 4, to allow for smoothing of the data across fluctuations in average temperature.

At the end of four weeks, multiply total weekly energy consumption by the net effective cost per KWh as reported on your power bill.

Joe Perez

iTrader: (8)

This suggests that I should use a 20' moving truck as my daily driver, since I occasionally move.

mgeoffriau

iTrader: (7)

Yes. This is why I always rent thermostats when I need one.

Scrappy Jack

iTrader: (2)

And I would not cite Sandy Eggo in particular for energy consumption due to it having some of the most desirable (and moderate?) weather in the nation.



I can believe that. I can also believe that many people don't think about it and don't bother with things like programmable thermostats - despite their ease of installation and use and potential money savings.

I may give this a shot for curiosity's sake, but I'm not sure how precise it will be given the "do nothing to change your energy usage habits that week" caveat. I'd guess our usage is relatively standardized, but there will doubtless be some variation.

Joe Perez

iTrader: (8)

Oh, absolutely. When we get a whole week of highs in the upper 80s and humidity above 60%, the local news starts talking about the impending apocalypse. Same thing happens when more than four consecutive raindrops fall within a 1 sq. KM area in under an hour.

Which is why I'm not comparing my own energy usage to that of the nation. I am comparing it only to that of my neighbors who live in the same area as I do. My implementing a $20 thermostat which I bought over a decade ago, I am clearly saving energy relative to my neighbors, and the data which I posted proves this.

It is fair to generalize that a person who implements a programmable thermostat in Houston or Birmingham will also save money relative to their neighbors. Maybe their electric bill will be $200 instead of $350.

Apples to applesauce.



Bingo.

We're accustomed to things like turning off our car when we park it, or switching off the oven after the food is cooked. We don't even have to think about these things- they just happen.

Ought to be the same for HVAC. But since it ain't, there's an easy solution which works well for most applications.

JasonC SBB

While looking at installing a whole-house fan in the new house, I wondered why home AC systems in our climate don't have a damper to suck in outside air for when it's cooler outside.

Joe Perez

iTrader: (8)

Some do. But this is considered sort of a "high end" option, not typically found on the sort of systems installed by the contractor in new tract homes.

Technically, these units are called "energy recovery ventilators" and are sold as a way to draw in "fresh" air and exhaust "stale" air, without sacrificing all of the cooling/heating work that has been done to the air already inside the home. IOW, it assumes that you are already running the A/C at a high level but that you wish to also exchange air with the outside, on the basis that "Poor ventilation may be harmful to your family's health" (quoted from one of the product brochures.) IOW, if you have a home which is highly air-tight, it's supposed to protect you from radon buildup, scary chemicals released over time from your paint and furniture, and other indoor pollutants.


It's basically just an air/air intercooler, which draws in outside air and passes it through one set of plates on the way into the home, while taking inside air and passing it across the other set of plates on the way out, hoping that there will be some beneficial transfer of energy between the two in the process. The efficiency is pretty low (they typically claim a 20% energy savings vs. just opening a window and letting all the cool / warm air escape that way) but it's better than nothing. Mostly, these are targeted at higher-end "green" mansions as a way of artificially masking the fact that they are consuming massive amounts of energy as compared to a normal home.





However, if you were to install such a system in a moderate climate, there's no reason at all you couldn't use it simply as an outside air fan (with the main A/C compressor switched off) when all you need is to draw in some cool air from the outside.

Links:

Energy Recovery ventilator | Heatexchange Unit | Air Conditioning and Purification | Eco Solutions | Business | Panasonic Global
http://www.renewaire.com/images/stor...ialcatalog.pdf
Performance Energy Recovery Ventilator - Carrier

Joe Perez

iTrader: (8)

Also, on topic!

I am really annoyed with myself. I just found out that there was an NRC public hearing last night up in Dana Point to discuss the re-start plans for San Onofre (refresher: the nuke plant near my home has been offline all year because of a secondary steam leak in what turned out to be some defective boilers that were put in a couple of years ago.)

As one would expect, it was deluged with anti-nuke protesters and other generally hysterical types.

I REALLY would have liked to go up there, stand up at the podium, and say "My name is Joe, and I have no association with the nuclear industry or any energy company. I live 15 miles from San Onofre, and I support the plant's re-start 100%. (Insert relevant facts to the effect that while I support Solar and Wind energy production as secondary energy sources, the fact is that we need reliable electricity even when the sun isn't shining and the wind isn't blowing.) When I go to bed each night, I like to know that my plug-in Electric Vehicle is being recharged with the clean, sustainable, carbon-free energy that San Onofre produces, and every day that it's off line is just one more day that we're needlessly burning through fossil-fuels and pouring tons of unnecessary pollutants into the environment."

czubaka

iTrader: (3)

Gotta throw a "Bitches!" in at the end of the speech.

flying_solo

iTrader: (5)

Do it Joe, I too support Nuclear Energy. I also support sending all the waste to Texas.

Joe Perez

iTrader: (8)

The point was that this meeting occurred yesterday, I missed it, and I no longer have the opportunity to do it.

flying_solo

iTrader: (5)

ahh, that sucks.

Scrappy Jack

iTrader: (2)

Another link for Señor Peréz as it relates to both San Diego and non-fossil fuel energy sources:

Algae Are a Growing Part of San Diego's Appeal - Businessweek

xturner

Hey Joe, here's a link

Help for Small Nuclear Reactors - NYTimes.com

Seems to me that factory-made sort-of-modular reactors would not be a new idea, but.....

When I was in the business, the cost structure involved in building a big nuke was what ultimately killed my project(and job). The idea of serially-made smaller reactors is too sensible to have not been considered before.

thenuge26

iTrader: (2)

Yes please. I mean this gets closer and closer just as our knowledge in materials and such get better/cheaper. Hopefully it's only a matter of time as far as bringing down costs.

Joe Perez

iTrader: (8)

It's weirder than that.

Factory-built Small Modular Reactors have been around for a quite a long time, in the form of Naval propulsion reactors. Those aircraft carriers and nuclear submarines couldn't wait around for lengthy on-site reactor construction. They never gained any serious interest within the civilian community, as it was assumed that large reactors would be more cost-effective in the long term, since they require fewer sites, personnel, containment structures, etc., per unit of electricity generated. It was also assumed that the cost of constructing them would tend to decrease over time, which Greenpeace et al made sure would never happen.

Puzzlingly, there has not, until recently, been much in the way of standardization for large reactors. From a licensing perspective, ever reactor presently online in the US has always been considered a custom-job. Specifically, operators have bee required to jump through two separate sets of hoops; first a construction license was required to start the project, and then after the reactor was built, the operator could file for an operating license.

Because of this, the construction of any new reactor was a massive financial risk. An operator might be granted the construction license and spend years and billions of dollars building the site, only to face new opposition when it came time to apply for the operating license. In fact, this very thing has happened several times in the US, which is why we have a number of mothballed reactors. Typically, these were units that were begun prior to 1979, but abandoned after the TMI-II incident made operators fear that they would never be able to receive an operating license once the reactor was completed.

This is kind of crazy, if you ask me.

Pretend that you are Boeing, and you build airplanes. Airplanes are far more dangerous than nuclear reactors in terms of civilian deaths per year. When a customer wants to buy an airplane from you, they don't have to jump through a bunch of regulatory hoops to prove to the FAA that the airplane is safe. You, as the manufacturer, have already done that. You built one airplane, subjected it to thorough and rigorous testing, and the FAA granted you a Type Certification. Once you have that, you can build as many copies of that airplane as you like, and sell them with a minimum of fuss.

Well, the NRC has finally gotten on board.

First, they have started issuing Design Certification on reactor families. So when Westinghouse came up with the new AP1000 reactor, they submitted it for review, and the NRC said "Yes, we agree that this reactor is well designed, and you may build as many of them as you like." Then then segues into the second concept, which is the Combined Construction and Operating License.

As a utility, if you elect to buy a reactor which has received design certification, you may file for a COL prior to construction, and provided that you follow the rules and the reactor is built exactly to spec, you may be confident that you will be allowed to operate it once it is complete.

This process is precisely how Vogtle and V.C. Summer have gotten to the point where they are finally constructing a total of four new AP1000 reactors. (Watts Bar unit 2, which is the fifth reactor presently under construction, was actually started in 1973, but fell into regulator hell after TMI, and was officially mothballed at about 80% completion in 1988.)


I assume that the reactor described in that article you linked to is the B&W "mPower" although it doesn't specifically say. mPower is actually a really interesting design, from a systems point of view. The underlying technology is pretty old school (it's just a plain ole' light-water PWR) but the packaging is pure genius. Rather than having a separate steam generator as an external component, the steam generator is built right into the reactor pressure vessel itself. Thus, there is no need for the large-diameter piping which traditionally carries primary-loop (radioactive) water out to the external steam generator (PWR) or turbine hall (BWR) in a conventional plant. The radioactive coolant never leaves the pressure vessel! And since the only thing leaving the reactor is steam, there are no penetrations at all below the waterline. You can break every single pressurized external pipe, and the primary coolant all stays inside the vessel.

The refueling process is pretty nifty as well. In a conventional reactor, you have to shut it down every 2 years, unbolt the huge lid, use a crane to pick up fuel and move it around, then bolt the lid back on. It's a hugely time-consuming task. With the mPower, the operator has the option to never even touch the fuel. You can run the unit for four years, then pop the whole reactor out as a complete assembly, drop a fresh one in, and send the spent unit back for refurb. It sounds almost comical, but it's the truth.

xturner

IIRC, the operating licensing process was concurrent with design and construction, so you had NRC, EPA and everybody else involved with the operator and AE, so that you weren't really betting $5B on a licensing deal dice roll 8 years down the road.

While TMI certainly ignited a flurry of nanny-ism, the financial effects might have been more important. My project (WPPSS 3 & 5 - we didn't call it "Whoops" for nothing) was set back severely. We went from something like 60% complete on unit 3 to 28% overnight due to NUREG changes; unit 5 went from 30% to around 15%. Retrofitting and redesign probably extended completion by 4 years and nearly doubled the final cost. And then, of course, you had Mt St Helens and ashfall issues to worry about......

The foks in Washington, as a group, had no special problem with nukes, even after TMI. The WPPSS nuclear program going from $7 or 8 Billion to $30 Billion and nearly bankrupting the whole region was another matter. That's why they were abandoned.