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Chasing down excessive power consumption

Discussion in 'General Electronics Discussion' started by GreenGiant, Jul 12, 2020.

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  1. Alec_t

    Alec_t

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    Unwire the individual live wire feeds to the smoke alarms. Is there still current in that breaker circuit?
     
  2. Tha fios agaibh

    Tha fios agaibh

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    I use a tonner to trace circuits but you can get away with just an ohm meter.
    Pull hot wire in question from the breaker and temporarily connect it to ground, then when you verify a dead circuit downstream, you will have low resistance from hot to ground. (or it's feed elsewhere)

    You may have to enter a jbox to farther isolate the loads downstream. Always verify circuit is dead before touching anything, and test your meter on a know power source beforehand. (so you can trust meter).

    Honestly I'd look at the big fish like central air or electric heating circuits before chasing tiny loads like smokes.
     
  3. Externet

    Externet

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    With the ownership of a house with 140 light bulbs I would had demanded and moved the hell until the seller/builder delivers ALL blueprints, electrical and not.
     
  4. GreenGiant

    GreenGiant

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    That is a fine suggestion, I hadn't even thought about doing that even though I have used that method in the past, I will have to try that out in the near future.

    To address the "big fish" at the moment there is only one central air unit, and I know that it is on a separate sub panel, as for electrical heaters there's only two, one in the oven and one in the dryer, and those are their own breakers (50A and 30A respectively, not sure why the oven is on a 50 though).
    The reason I'm chasing these smaller loads is because the total constant load 4-500W:
    ~120W for my network stack (I have already put in a hibernate schedule for my NAS which will bring the average down to ~100W)
    ~100W for my furnace for some reason (working on this one too)
    ~65W for various IoT devices
    ~160W for my smoke detectors, but turned out to also be a chest freezer that runs on a 20-30% duty cycle so this is really ~85W (~50W on the smokes, and 35W for the freezer)
    ~75W for a humidifier running at a ~10% duty cycle (45 min to an hour every 6-10 hours)
    And a few other very small loads that I will eventually look further into that are <5W total

    Hence originally chasing the smokes since that was the largest single load, they are still concerningly high, but furnace and possible freezer replacement are next on the list, and maybe adjusting settings on the dehumidifier.
     
  5. hevans1944

    hevans1944 Hop - AC8NS

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    Did your solar power installation include the ability to sell energy back to your electric utility during the day, through an inverter connection between the solar panels and the grid? That's what many folks here in southwest Florida do. They get the PV panels installed for free and lease them through a third party. Florida Power and Light (FPL) installs a meter that can run "backwards" when the solar panels deliver excess energy to the grid, through an inverter synchronized to the grid frequency and phase.

    Well, the meter doesn't really run backwards. It has no moving parts at all, being a "smart" meter that FPL can read at will. FPL can also shut off power to the house using this "smart" meter if their bill isn't paid. And if we allow FPL to shut off certain other things... like the water heater or air conditioner... during certain times of the day, FPL will pay us for that. They pay even if they don't have to shut anything off, such as to avoid "brown outs" or rolling "black outs" which we have yet to experience. Thinking about signing up for that.

    There is no battery storage of the solar-generated electrical energy, so in the evening, at night, and in the early morning hours FPL supplies all the energy to the home. If there are enough solar panels, it is possible to see a net gain in energy during the day, after deducting the cost of air conditioning. Selling excess energy back to FPL is supposed to amortize the lease on the solar panels, but your mileage (or kilometers) may vary.

    I can believe you might have an average power usage of ~0.7kW, or about 700 watts, "all night every night," except for [power] "spikes when the central air kicks on." But what's with the kwH (presumably kilowatt-hours) designation? That's an energy unit, NOT a power unit. You don't consume power because power is the rate at which energy is delivered to you from the electric utility. Or, sometimes if so equipped, the rate at which you sell energy back to the electric utility. You consume and pay for energy, not power.

    The utility may pay you for whatever energy you contribute to the grid, but their rate of pay per kilowatt-hour is significantly less than what they charge you per kilowatt-hour to provide electricity from the grid to your house. Without some form of energy storage of electricity, to run things at night, it's difficult to break even with solar power, even if you can sell excess energy back to the utility operating the grid during the day.

    It says on your profile that you are an electronics technician working at a (rather famous) battery company, but here you claim be an electrical engineer. No EE that I have known would ever confuse power with energy. We learn, almost from infancy, that a watt-second is a joule, which is the MKS unit for energy. A watt, in a purely resistive load is just the voltage drop across the load multiplied by the current through the load. And of course a second is a well-defined unit of time. Scaling up to kilowatt-hours, we find one kWH is equal to 3,600,000 joules.

    Okay, lets assume you mean watts when you mention "1.2wH to 40wH of power" but how did that become "170wH (170W?) of total idle consumption?" 170 watts is a LOT of Echo Dots and Google Homes, some hi-resolution wi-fi cameras, etc. Maybe one of those "etc" devices pulls down most of those 170W of power?

    Whatever, let's just assume that particular branch circuit is using energy at 170W rate, constantly 24 hours per day, seven days per week, fifty-two weeks per year, ten years per decade, and ten decades per century. I won't add up how many kilowatt-hours of energy that would be for a century of use, but since your electric utility bills you on a monthly basis, that would be about 730 hours of continuous use per month, figured like this: (365 days/year) * (24 hours/day) / (12 months/year) = 730 hours per month.

    So, for your "smart home" items, drawing 170 watts continuously, their monthly energy consumption is 170W x 730H = 124.1kWH.

    I can see a network stack with an NAS pulling down 120W easily, depending on how many hard disk drives you have installed. I am typing this on a desktop computer, one of two I built about six years ago, that uses an Intel Core i7 CPU and 16 GB of DRAM on an ASUS P8Z68-V PRO/GEN3 motherboard connected to a 1TB hard disk drive and a 128GB solid-state-disk drive, all powered by a Corsair AX850 power supply that isn't even breathing hard yet. This rig has plenty of room for expansion with more disk drives and third-party high-performance video boards, so I may have "over-designed" it for simple home use.

    It wasn't quite on the "bleeding edge" of state-of-the-art personal computing "way back then," (dedicated gamers have deeeeper pockets) but these two desktop computers have held up well for how my wife and I use them. So again, whatever, let us assume your computer rig is pulling energy at a 120W rate and you leave it on all the time. The monthly energy consumption is 120W x 730H = 87.6kWH.

    Next, you mention your oil burner draws energy at the rate of 100W, "even when not in use," and ask "is this normal?" This is a question best answered by the manufacturer of your HVAC system. It sounds about right to me, but I have not inspected your oil burner, so please do find someone who can inspect your burner and render a professional opinion.

    In the early 1960s, my parents rented a house in Dayton, Ohio that was heated with oil. IIRC, there was a fan that fed forced air into the combustion chamber, and a high-voltage transformer that created an arc to light the oil vapors. There were other things too, of course, to determine when to turn on the pump that pressurized the oil, when to energize the high-voltage transformer to light the oil vapor, when NOT to leave the oil pump running if the oil vapor didn't ignite, etc. Lots of safety features, all of which required electricity to function. So, I would not be surprised if the "normal" power demand was about 100W, whether the house was being heated or not. This would surely increase if the furnace started burning oil to heat the house. The oil pump probably needs a few hundred watts, as does the blower fan. There are all sorts of oil-heated furnaces, so you would have to seek details from the manufacturer of your HVAC system concerning their energy requirements, both during active as well as standby conditions. But let's just assume your figure of 100W is correct so the monthly energy consumption is 100W x 730H = 73kWH.

    And finally, you mention you have ten hardwired smoke detectors located throughout the house and their total electrical load is 160W, which is 16W per smoke detector. We have a similar arrangement in our Florida home, but with fewer detectors: one high in the vaulted ceiling of our open floor-plan "living room," and three more, one in each bedroom, for a total of four. Our smoke alarms are all wired with low-voltage AC power AND backed up with a 9V "smoke alarm" battery that gets replaced (or should get replaced) every year. There is a green LED on each detector that is constantly on, and a red LED that flashes periodically, perhaps to remind me to change the 9V battery. Whatever, I doubt any of my smoke detectors draws 16 watts to operate, or even a tenth of that. A few milliwatts is probably more likely. You should closely examine your smoke detectors to find out why such a large amount of power is being demanded. Unless your measurement was completely wrong, something is not right with your smoke detector system.

    But, if we just assume you didn't screw up when you measured the power, the smoke detector monthly consumption of electrical energy is: 160W x 730H = 116.8kWH.

    I added all the figures that I highlighted in red in my response above, and arrived at 401.5kWH, which is significantly different from your estimate of 438kWH. I don't know where your multiplier of "0.6kwH" came from. I agree that either number is a huge percentage of your normal average monthly usage of 650kWH, but are you really only using 250kWH every month for everything else that uses electricity in your house? I just looked at my most recent FPL bill as we enter the summer cooling season... here in Venice, FL, the cooling season is all year, but some months are warmer than others... and I discovered we purchased 2654kWH of electricity last month. That is slightly more than we used over the same time frame last year, and more than four times your monthly consumption of electrical energy. So how much did those solar panels lower your monthly usage of electricity? And how much did it cost you?

    Yeah, don't we all? I do envy your 650kWH monthly energy usage and I wonder what it was before you installed solar panels? Maybe the cost of heating oil will jump to $500 per barrel this winter to compensate.:D

    You have already received some good advice here from other EP posters on how to "go about chasing down who is consuming this extra power". You need to verify that this is really occurring by narrowing the list of suspects down to individual circuits that you can disconnect by turning circuit breakers off. If you find something suspicious, disconnect it from the branch circuit it is on and measure again. Always measure the current in a branch circuit at the circuit breaker using your clamp-on ammeter. After you have disconnected every known load on a particular circuit breaker, there should be zero current measured. If that isn't true, you need to find out what is "stealing" current from that branch circuit. Perhaps injecting a "tone" on the branch circuit with the circuit breaker turned off will assist you in tracing the fault, or at least help locate the wires connected to the fault.

    Hiring an electrician is always an option, but you need to determine that a problem really exists before bringing in expensive outside help.

    The easiest way to minimize your monthly energy usage is to increase the insulation in your house. Find several contractors who know what they are doing and get quotes. Ask neighbors for recommendations. Adding insulation can be expensive, but it will pay for itself in the long run by reducing heat gained during the summer and heat lost during the winter.

    Thermally insulated and efficient windows help a lot to minimize heat gains and heat losses, but they are expensive solutions.

    Getting rid of all or most of your incandescent lamps as well as the "curly bulb" fluorescent lamps was a wise move. We only had forty or so to replace when we moved here in 2016, but most of our lamps are now LEDs. Up north I was sometimes glad to have incandescent lamps because of the heat they gave off, but here in semi-tropical Florida they just aren't welcome.

    Please let us know how your search goes.
     
  6. GreenGiant

    GreenGiant

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    Yes I have a net meter that tells the provider (National Grid in this case) how much I have provided to/taken from the grid, and in general I have been net positive in generation, currently I have generated 3.5MWh and consumed 2.6MWh, netting export of ~950 kWh.
    I was considering batteries, but due to the lack of reduced rate hours and the prohibitive expense of them I decided to not get any.

    It has been many a year since I have created this account, and had since moved on to a few other jobs, to be honest I had forgotten it mentioned anything about job/title on here, since creating the profile I got my degree and have been an electrical engineer for 7+ years working mainly on automation systems, not directly dealing with power consumption aside from full load amps and the like. That coupled with the fact that I was writing this at 10PM after working a very long few days and as I have mentioned in a couple replies I had over-compensated when converting to easier to digest international numbers, as I had recorded in Amps but unless mentioning I was on a 120V supply current is rather meaningless. To be fair I have explained the idea of Wh and kWh to people for their understanding, so as mentioned was purely a slip up of units.

    As I said, there are various circuits drawing from 1.2W to 40W fairly constantly, (Ring flood camera x 2 is about 18W, 3 echos combined at ~10W, 3 google home minis combined at ~6W, Philips Hue lights and bridge combined at ~15W, 4 Nest thermostats at ~4W, a couple displays combined to 15W and a few others that I am sure I am forgetting for smart home devices. The remaining 100W is other things, a couple printers on standby probably drawing 5-10W apiece, a couple Rokus drawing 3W apiece, and other things that I am not sure about but are just various circuits with small amounts of current draw.

    I did have it serviced last year, though electrical was not part of it, but it started/stopped appropriately.
    The manufacturer to my finding does not offer a standby power consumption rating, but does mention that power consumption should be between 100 and 200 when active, and break it down further to say that circulator pumps will draw about 100W and the zones valves will draw about 10W each. I measured it at about 280W running, with one pump and one zone active, so it does draw a little more than it is supposed to it seems. I have confirmed that it is the only culprit by turning it off at the boiler (service switch) and consumption drops to 0 on that circuit.

    I have mentioned an amendment to this that overall the smokes are consuming about 50W which is still far above what they should. This is the main circuit I am focusing on first to troubleshoot excessive draw.

    I would argue that the figures are not that far off, less than a 10% difference. Admittedly I have done some rounding to get to the 550, looking at the detailed numbers on my end it comes to 591W of total draw, so i rounded up to 600W for easier/cleaner maths and similarly I rounded things up or down to make the math a little more simple since I am not super bothered by a couple of Watts, moreso the overall picture.


    They have lowered my bill by about 150% at this point, which is in line with the sizing of them (140% of my average usage), summer being the higher amount used, and the higher production months.
    They were pricey at about $30k but theoretical payback is going to be 6.8 years from installation according current average use and cost of the system.


    The 650kWh is my average consumption BEFORE panels, which is still nearly double what some of my family members use (two households use around 375kWh another uses around 450kWh average per month), while my wife and I try to be diligent about lights, we hang dry clothes when possible, and things like that.
    Per your heating oil comment, Heat Pumps are going in starting on the 27th of this month for supplemental heat and adding AC to the house, so this winter I will hopefully use next to no oil anyways!
     
  7. GreenGiant

    GreenGiant

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    Quick update, turns out the Nest's were causing the Boiler Manager to function erroneously and keep the circulator pump on at all times. The boiler manufacturer suggests that you use one of two options when connecting them, use a three wire connection (24VAC power, signal and common) OR when using two wire, add in a resistor (200 ohm 15W) between the signal connection and common at the furnace side. Fortunately I had a handful of high wattage resistors lying around, and was able to test it out (ordered the correct ones at $0.95 apiece) and it shuts off when there is no heat draw, dropping power consumption to just under 10W.
    Not accounting for actual running power, this is almost 10% of my total idle power usage, now onto the smoke detectors and other smaller draws.
     
  8. Bluejets

    Bluejets

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    I can foresee smoke on the horizon.
     
  9. GreenGiant

    GreenGiant

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    Hey now, play nice...

    All the detectors have batteries that aside from 2 have been changed yearly, those two are just very inaccessible, so it has been almost 2 since they have been changed. The point being that they will still function even if not plugged in for a short time.
     
  10. hevans1944

    hevans1944 Hop - AC8NS

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    Does National Grid credit you on a 1:1 basis for energy provided by your solar panels to their grid? In other words, if you send them one kilowatt-hour of energy, and then later consume from their grid one kilowatt-hour of energy, is that a "break even" no-cost-to-you arrangement? Or do the rates depend on the time of day? I had heard or read somewhere that it wasn't an equal exchange because the homeowner doesn't bear the overhead costs needed to maintain the grid, so the utility "buys" energy at a lower price than they sell it to homes. I don't think it matters whether your "excess" power delivered to your grid-tie comes from windmills, solar panels, or a Mr. Fusion plant you bought second-hand from some wild-haired guy driving a beat up DeLorean automobile, advantage is to the utility.

    Still, amortizing $30,000 in less than eight years through energy savings provided by your solar panels, sounds like a great deal! You will need to keep them properly maintained of course for maximum efficiency: clean, free of leaf debris in the fall, snow in the winter and pollution sublimated from the air, but that shouldn't be too difficult if the panels are easily accessible. Maybe just hose 'em down with water once in awhile?

    I read an article (in "Nuts and Volts" magazine IIRC) about someone who did a massive solar panel installation at his isolated house located in a Northern forest. He mounted the panels high on two telephone poles at optimum angles to the sun and adjusted the angle twice a year. I think he mentioned plans to add a motorized elevation adjustment. IIRC, this guy was totally "off the grid" so he did have to provide some battery storage for his panels for use at night.

    In accordance with good telephone practice (a century worth of experience there!), lead-acid batteries need to be stored and maintained in a separate, well-ventilated, brick enclosure. Not sure if there are any copper-wire telephone "central offices" still in existence, much less any need for 48 V DC battery supplies to run the telephones, but this guy was so far off the beaten track he had no telephone. Survivor type, I guess, or maybe he just wanted to be left alone.

    Back then (about twenty or thirty years ago) monocrystalline silicon photovoltaic panels were rather pricey. Today, PV panels are more affordable. For example, this Tesla 325 watt panel sells for $255 each in minimum lots of ten. Fifty of those might be enough to make an installation here in Florida "pay for itself" in just a few years, depending on how much FPL will pay me for energy I feed back to their grid. Wife thinks we should instead go the "free installation and lease the panels" route, but I worry about roof maintenance, especially after hurricane season. I would rather install the panels on the ground with mounts that can be seasonally adjusted for best performance. However, more study and research is required.

    Sixteen kilowatt (or greater) grid-tie inverters are not a problem anymore, so I should be able to do a PV panel installation similar to yours for around $30,000. Everything we do here in Florida requires a permit and an inspection, and sometimes a study to make sure you aren't harming the local wildlife habitat, or water-draining channels that are necessary to control flooding... which is frequent during hurricane season. Those permits and studies and inspections can significantly increase the cost of any project, but the penalties for ignoring them are Draconian... like triple the original permit fee and the county sheriff enforcing the demand that you to tear down and start over.

    As for energy storage... we ain't there yet. Batteries are a real PITA to maintain and expensive to install and replace. That's why the electric car revolution hasn't happened yet. Your decision not to go there with your solar installation is well-advised at this time.

    To date, the most efficient way to "store" electrical energy is to use it to pump water uphill into a reservoir (a dam), creating potential energy, and then drain the reservoir through water turbines driving high-voltage alternators to recover the electrical energy. Think "Hoover Dam and Lake Meade" for the scale of what you need to be efficient, although I don't think the Government does it on that scale yet, because the Colorado River provides the water refill when Hoover Dam extracts energy by taking water from Lake Meade. There are other (smaller) dam-and-pump installations where electrical energy is stored, but the real estate requirements prohibits much widespread use. This method of electrical energy storage has been around since the 1890s (in Italy and Switzerland) and is called pumped-storage-hydropower.

    Understandable about forgetting what we wrote way back when. I hope none of my stuff comes back to haunt me. Congratulations on completing your engineering degree!

    Please don't make the same mistake that I did after graduating in 1978. If you haven't done so yet, apply NOW for an Engineer-in-training certificate, find a PE mentor, join a few professional societies like the the IEEE, and get your Professional Engineer license. You may never need a PE license, but if you do, it is easier to pass the PE tests while relatively young rather than later.

    All of my engineering career was spent working for companies that held contracts with the Department of Defense. The DoD doesn't care if you have a degree, if you can do the work required. The DoD doesn't care if you have a PE license, if you can do the work required. But working without a PE license for companies whose sole source of income is the DoD can be risky business for you. I found out that here in Florida after I "retired" from my last job. I cannot practice engineering here without a PE license... unless I work in certain "exempt" areas associated with the Space Program on the East Coast, or for a satellite communications company. I cannot be "self-employed" and offer electrical engineering services here without a PE license.

    Sounds like you are doing a pretty good job narrowing down what loads are "stealing" current. Since you are doing a "smart house" you can probably put all your loads on "smart outlets" that you can remotely enable and disable, although it's probably not a good idea to do that with something like a printer. My ancient HP 6600 Officejet printer takes about fifteen minutes to recover from a power interruption. If I were to get a Xerox solid-ink printer (which I really like) it would be at least an hour to warm up the wax-ink reservoirs so I could print again after cooling down. It would be hard to justify leaving such a beast on 24/7/365 consuming energy without producing any output. My flat-screen TVs do this all the time, but I don't think it amounts to much. Maybe I should measure it and find out...

    Yep, I would definitely continue to look closely into that. I see no reason why a well-designed smoke detector shouldn't draw much less than a few milliwatts of power. After all, without an AC line supply, the average smoke detector will operate for one year on a single 9V "smoke alarm" battery... the size we used to call "transistor radio" batteries. Adding an AC supply to allow a "confidence" LED to light up continuously shouldn't require more than fifty milliwatts.

    Sure, engineers round measurements all the time unless some accuracy spec is involved. Even then, getting a "ball park" estimate is valuable as an indication in which direction to either proceed or abandon a project. I think we are both on the same page here.

    Good idea on the heat pumps. They are used more than I expected here in Florida, probably because the air stays warmish all year so the heat pumps are uber efficient. We don't have a heat pump, but we only had to turn on the resistance-heating HVAC function ONCE last winter, and then only to offset an unexpected chill. One gets used to the heat pretty quickly (at least I did) when living in southwestern Florida near the Gulf coast, so with any sudden drop in temperature it feels very cold. What I considered shirt-sleeve weather in Dayton, Ohio would cause folks here to bundle up in their "winter" clothing.

    Please let us know how your solar installation fares in the months ahead. I've been wanting to install some form of solar energy collection for years now, but have never had the proper incentive. A few years ago (quite a few, actually) one of the places I worked at as a technician was developing low-temperature phase-change heat storage materials based on some sort of polymer. The idea, I think, was to use solar energy to store heat in this material and later release it into thermopiles for electricity generation. Might have had some practical use in outer space applications, but I don't think anything became of it.

    Then there was another solar project out West somewhere that was using sun power to melt salt for energy storage... with an array of steerable, flat, mirrors to concentrate the sunlight. I think the molten hot salt was used to drive a steam turbine for electricity production. Now that might have a practical application for home use if scaled down in size, although it would still require some large area to collect the solar heat energy. Here in Florida they do use solar heat to warm swimming pools, and sometimes to pre-heat water for hot-water tanks. But FPL sells electrical energy so cheaply that it is hard to justify solar panels that do nothing more than warm up water.
     
    Last edited: Jul 20, 2020
  11. GreenGiant

    GreenGiant

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    So there are no reduced rates at night or anything here in MA, it appears that it is a 1:1 rate, so every kWh I produce is credited, and then during the winter when production is slightly less I would draw from that credit and still not have a bill, National Grid gets a lot of incentives for moving to green energy so even though they aren't making the money off my electrical consumption they still are getting something from it.

    I agree with both statements, batteries are getting close when it comes to grid storage (which will increase the efficiency of the grid as a whole by a good 10-20% on its own right). Look at Tesla's batteries in Australia essentially paying for itself in the first year or two, just incredible.
    The water tower/mountain model is a good one, and clever too, but not really something I could set up in my back yard easily...

    I do appreciate the information, but I was never very interested in IEEE, after looking at it, I didn't find it worth the time/money, this is for me personally, I have never been a fan of communities like that in general.
    As for PE license I was considering it, but I just don't think it is worth the time, money or effort. I actually recently moved to a non-engineering job, since I hate the process of engineering. I am much more of a "try anything once or twice and take risks" type engineer (commonly known as the mad scientist version), where most of my time in my engineering jobs were spent in endless useless meetings and doing useless paperwork. The last place I worked had a process for putting through an ECO (engineering change order) that at minimum took 3 weeks, and that was if everyone was in the office at the time (internal network was inaccessible out of the office due to security concerns) and there were no questions/concerns about the change. That was my experience with engineering for the last 7 ish years, and I was miserable, actually working on stuff is much more my desired work life.

    They are both for heat and cooling, since my forced hot water/oil heat is vastly undersized for the house and location in MA in the winter, the boiler will run for hours and only result in a couple degrees of warming (I usually keep the heat set to 64-66 in the winter, but on those very cold days there are times where a little warmer would be nicer)
    Actually fun fact the Nests that I have are almost detrimental to energy savings in the winter, because I was frequently out of the house for work it would turn the heat off and know about when I was coming home and pre-heat so it was warm for when I got there. But the timings were so bad that I left the house around 5 ish in the morning and got home around 5 in the evening, the heat would be off from 5:30/6 until 1PM then run a pre-heat until I got home, when maintaining the heat at 64 would probably have been more efficient.

    I have heard of that project, very interesting idea that does make sense and the only real exhaust would be nothing but steam. I have seen people create small heaters out of the fresnel lenses from older projection TV's.
    There was also a video I saw years ago of some UK research facility with focused sunlight (two square meters I think) focused to a very small spot, and it was enough energy to melt stone. There is so much energy coming from the sun, I have often wondered why we don't use that for a method of steam production for steam turbines and the like.
     
  12. hevans1944

    hevans1944 Hop - AC8NS

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    What!? You have never heard of making mountains out of mole hills?:eek:

    I can definitely relate to that. I was always a "hands on" engineer, and a pretty damned good electronics technician before I graduated college in 1978 with a Bachelor of Electrical Engineering degree. I cannot imagine doing real engineering work any other way, although most of my employers would disagree. I was somewhat of a maverick to them, bull-headed, difficult to supervise, but useful for "getting things done," so they put up with me for many years.

    I have always believed that if you aren't having fun in your job, you need to find another job. Except for brief periods of unemployment in the 1990s, all my jobs have been a lot of fun. And they all have involved hands-on engineering with some technician-type activity thrown in. I recently retired from operating and maintaining a particle accelerator from 1996 to 2014. I talked my way into that job at the last minute without ever seeing or even knowing exactly what a particle accelerator was, much less what it was doing at a little dinky company at the edge of a country club golf course in Beavercreek, Ohio. That wasn't all I did (eventually), but that was what I was initially hired to do. The other things I did for the lab where I worked were fun projects that I did when not implanting ions into semiconductor wafers... among other things and targets. One fellow wanted us to make "black diamonds" by implanting oxygen ions into their surfaces. These were cut gemstones of poor quality that he hoped to "improve" by coloring them. My boss and I wasted months of "spare time" on this with totally negative results, although IIRC we were able to turn the surface of cut diamonds into amorphous carbon, further decreasing their already low value. Turns out what this guy wanted to do (produce colored diamonds) is easily accomplished by exposing the stones to neutron radiation from a nuclear reactor. Easy, peasy if you have one of those in your lab, which we didn't.

    This puzzles me too. The Sun provides about a kilowatt per square meter, so it would seem practical to set up mirrors to concentrate sunlight on a boiler to make steam to operate a turbine that drives an alternator. Maybe the thermal efficiency is just too poor to compete with gas-fired or oil-fired or coal-fired boilers at this time. I will look into it, maybe build a small solar heat concentrator to make steam or at least some very hot water to run some sort of alternator connected to a turbine... maybe use a Tesla turbine, which doesn't require any turbine blades.

    In Dayton, there used to be a large power station (Tait Power Station) with at least four coal-fired boilers and four huge brick chimneys. This station was located next to I-75, on the west side of the highway, between the highway and the Miami River. There were railroad spurs adjacent to a large coal yard that kept this plant fueled 24/7/365. The plant was eventually torn down and replaced with natural-gas fired turbines connected to alternators that served as "topping" generators. AFAIK, all the coal-fired steam plants in Dayton shut down years ago, but low-pressure steam was used for many years to heat the buildings in downtown Dayton. A goodly part of New York City is still heated this way, a system called district heating.

    Steam is an interesting critter, especially super-heated steam which is a gas without liquid water content. Unsaturated in other words. It is easy to store super-heated steam in insulated underground reservoirs with little loss of energy. And it is fairly easy to make such reservoirs in usefully large volumes using low-yield underground nuclear explosions. AFAIK no one has ever exploited that technology since it was demonstrated in the 1950s. Probably because there are cheaper and less hazardous ways to create and use energy. Plus, I doubt there are any civil engineers left alive that know how to make an underground, glass-lined, spherical chamber using a nuclear bomb. But your Uncle Sam did thoroughly investigate this, and maybe sometime this century the details will become unclassified. Methods and means will still be highly restricted of course, as they are for any "special nuclear materials."

    I discovered that Tesla now sells a home version of their car battery with an inverter/charger, called a Tesla Powerwall. Their website suggests that I need four of these puppies and a 16.32kW solar PV installation, based on my average monthly cost of $260 for electricity. Cost would be $29,000 installed and Tesla would pull all the permits and coordinate with local authorities for the installation. That's just the cost for the Powerwall. The solar PV installation would be separate. It is an attractive option if I decide to invest in solar PV panels and buy enough panels to ensure I always have a net energy flow back to FPL. The area where I live is one of the most sun shiny places I have ever seen, and that includes places out West like Arizona, New Mexico, and Texas. Lots of sunshine here, and FPL is taking advantage of it by building their own PV panel farms.
     
    Tha fios agaibh likes this.
  13. GreenGiant

    GreenGiant

    842
    6
    Feb 9, 2012
    Been a while, but the latest updates:
    Had two smoke alarms die completely, replaced the batteries but still non-functional despite only being a couple years old.
    Did some digging and one of the 9 in my house was just about to the end of its life (8 years old) and three of them were not wired correctly anyways (instead of using a red wire for communication they were using the ground wire, which was not connected to anything else, but still not wired correctly).
    I decided to replace them all with Nest Protect smoke alarms so they do not use the red wire anyways.
    The only drawback to the Nests are that they do not meet code in MA since the garage needs a dedicated heat sensor not a smoke detector.

    Measuring the current after replacing them it is down to a 7W draw instead of the original 50W, so a fair reduction in power consumption.

    Now the current main consumer of power is the heat pumps, which in the summer are not bad, a nice sunny day will produce more than enough to overcome the draw of the AC's. For heat though the power draw is greater than even the sunniest of days, so I'm trying to find the best balance of indoor temperature to power usage.
     
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