Energy independent housing

http://www.anzwers.org/free/energy1/Energy_independent_housing.htm

This system can be produced tomorrow..
It can utilize a day of great wind...
The salt can be isolated under vacuum very well because this vacuum can be produced between
strong materials..

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Energy independent housing

    I am not sure why you are trying to talk about melted NaCl (Table Salt) and Flywheels here...

    Flywheels for decades have been looked at for efficient storage of power--however their size, potential for self distruction and efficiency issues (bearing, drag, conversion, etc.) have, from what I have read, pretty much limited flywheels to short term power storage (i.e., flywheel on motor generator set to carry power over until a prime mover can take over).

    Regarding the melting of salt--it melts around 800.8° C (1,473.4° F)--That is somewhere around cherry red to orange read for steel/iron. At those temperatures, you are talking about very high technology. materials to transfer energy to and from the salt pot. Let alone the issues of losses due to thermal re-radiation. And, I don't believe that salt transfers heat (low thermal conductivity) very well--it seems like it would be very difficult to transfers large amounts of heat flux via salt without using some sort of molten metals or molten salts.

    It is possible to build something that could store and release the energy using salt--but at 1,400 degrees I don't see how it can be gathered though direct solar radiation--only through (lossy) electrical (or chemical and/or mechanical) means could you heat anything that high. And, again, finding reasonably priced materials that have good mechanical strength at 1,600-2,000° F.

    Given that electric utilities are always looking for efficient "peaker" plants (the difference between a long term steady load and the 2x loads that they serve in the afternoons and evenings), if this was such a great idea for wind power--it would be a wonderful solution for utility companies where they would only have to store a few hours of energy instead of days of energy like an off-grid home would have too...

    I believe that there are folks working on molten salts storage batteries--but that is a different concept than you are suggesting on your web site.

    Do you have links to sites where molten salt has been successfully demonstrated as an energy storage system?

    Right now, the US government is experimenting with liquid "salt" systems... However, this is not NaCl, but a mixture of other types of salts that melt at about half the temperature of table salt (operating temp of ~565° C). If you wish, follow the link below to see what is being done right now...

    http://search.nrel.gov/query.html?col=eren&qc=eren&style=eere&qm=1&si=0&ht=815081754&ct=1790951786

    But, today, the cost per kWhr of these systems for energy collection (solar tower) and production is around $0.10 to $0.14 per kWhr--sounds OK until you see that current utility costs for electric power is in the $0.04 per kWhr range (although, at the upper end of the electric rate charts, they charge between $0.11 to $0.21 per kWhr). The rest is for distribution and other charges.

    http://www.pge.com/tariffs/pdf/E-1.pdf (go to page two for unbundling of rates)

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Energy independent housing

    platini,
    i for one would like to know where it is you are going with much of this as most of it is just hyped up, theory, or experimental? as an example this is from your website:
    "A big hole in the ground having a ray around 1000 m. receives around 12 million kwh of solar energy per day."
    now it is common knowledge that each square meter receives about 1000 watts of solar energy(1kw) and that in a day this may be in rare instances about 7 hours worth of full sun(1000w per sq meter). even an idiot can see that your big hole is not receiving 12 million kwhrs per day and even if it did receive it, you would have conversion losses to deal with in getting the electricity from the sun's energy no matter what way you'd try in converting it. as bb stated people do use some of the methods and materials mentioned, but there's no panacea. if you have done work in the areas you mention, that is fine as you are welcome to share real results with everybody here. nobody likes wild or exaggerated claims like everybody would see from shysters and the only reason your posts weren't deleted is because i saw no eveidence of selling something or a link to something else for the selling of something. i don't know if naws would authorize the deletion of posts that are purposely deceiving others with wrong info, but i and others will certainly put our 2 cents in to set records straight. it would be nice if you started backing up your claims and statements rather than tossing something out there that is exaggerated (mildly putting it) be it good intentioned or not. in other words, before naws looks upon the disinformation as detrimental to their solar business or hears of customers complaining due to false expectations and decides your posts cost them and others in any way, then you should be more truthful in your posting. this does apply to your website too because you keep refering to it in your links. all it would take for me to want to delete your posts would be 1 report of somebody buying a square meter's worth of pvs and using mirrors on it and expect to get 12 millionkwhrs/1000m=12,000kwhrs in a day. get my point?
  • System2
    System2 Posts: 6,290 admin
    Re: Energy independent housing

    Steel is produced at high temperatures utilizing strong durable low cost materials.
    The problem of heat transportation is solved using the heat of vaporization
    of sodium( boiling point: 880°C ,  heat of vaporization : around 1000 kwh/m3)...
    it only needs to be moved..









  • System2
    System2 Posts: 6,290 admin
    Re: Energy independent housing
    niel wrote:
    platini,
    i for one would like to know where it is you are going with much of this as most of it is just hyped up, theory, or experimental? as an example this is from your website:
    "A big hole in the ground having a ray around 1000 m. receives around 12 million kwh of solar energy per day."
    now it is common knowledge that each square meter receives about 1000 watts of solar energy(1kw) and that in a day this may be in rare instances about 7 hours worth of full sun(1000w per sq meter). even an idiot can see that your big hole is not receiving 12 million kwhrs per day and even if it did receive it, you would have conversion losses to deal with in getting the electricity from the sun's energy no matter what way you'd try in converting it. as bb stated people do use some of the methods and materials mentioned, but there's no panacea. if you have done work in the areas you mention, that is fine as you are welcome to share real results with everybody here. nobody likes wild or exaggerated claims like everybody would see from shysters and the only reason your posts weren't deleted is because i saw no eveidence of selling something or a link to something else for the selling of something. i don't know if naws would authorize the deletion of posts that are purposely deceiving others with wrong info, but i and others will certainly put our 2 cents in to set records straight. it would be nice if you started backing up your claims and statements rather than tossing something out there that is exaggerated (mildly putting it) be it good intentioned or not. in other words, before naws looks upon the disinformation as detrimental to their solar business or hears of customers complaining due to false expectations and decides your posts cost them and others in any way, then you should be more truthful in your posting. this does apply to your website too because you keep refering to it in your links. all it would take for me to want to delete your posts would be 1 report of somebody buying a square meter's worth of pvs and using mirrors on it and expect to get 12 millionkwhrs/1000m=12,000kwhrs in a day. get my point?

    In Europe on average there are around 4 kwh/mq of solar radiation per day.
    A circle having a ray of 1000 m. has a surface of pi * r^2 = around 3 millions of mq therefore
    this big hole in the ground receives 3E6 X 4 = 12 million kwh per day!
    In a year it's around 12E6 X 365 = more than 4 billion kwh per year!
    (Spain: 1800 - 2000 kwh/mq per year, 1800 X 3E6 = 5,4 billion kwh per year)

    If the global efficiency is around 25 % then this solar furnace..would produce 1 billion kwh per year!
    This calculations are realistic!!

    I am not joking!!!!
  • Roderick
    Roderick Solar Expert Posts: 253 ✭✭
    Re: Energy independent housing

    The figure for insolation on a hole 1000m in radius seems reasonable. However, this would be a very large hole, 2 km in diameter. It exceeds the size of the Arecibo radio dish, and is bigger than many sports stadiums, parking lots included. Seems like quite a construction project.

    I'm more interested in small systems, and if you had something that could work on a single residence scale, that would be interesting. I would think that storing energy as heat would be the last choice, and one would only do it if one could afford to throw away a large portion of the original energy, as the 2nd Law of Thermodynamics would penalize you going in, and again coming out, of your storage.
  • System2
    System2 Posts: 6,290 admin
    Re: Energy independent housing

    The problem of energy storage is great.
    Compressed air stores around 2-3 kwh/m3, a flywheel having 1 m. of ray stores around 1 kwh etc...
    The latent heat stores a lot of energy, an example is the same heat of vaporization of sodium that
    stores around 1000 kwh/m3 (1 m3 of hydrogen at 300 atm. stores the same quantity of thermal energy..).

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Energy independent housing

    Just doing some rough back of the envelope calculations, the US (Europe's (EU) numbers are similar) total energy consumption (fossil and nuclear fueled--ignoring the small solar/geothermal:

    http://www.nef1.org/ea/eastats.html

    88 x 10^15 BTU or x3.413 = 300 x 10^15 whrs of fossil fuel for 1 year of US energy (1999)

    300 x 10^15 wh/yr / 5.4 x 10^9 kWhrs/yr = 55.5 x 10^3 or about 56,000 of these "stations" (using Spain's numbers)...

    So, if I have my math right, it would take, roughly, 50,000 of these stations for Europe, another 50,000+ for the US, and another 50,000+ for Asia would supply equivalent amounts of energy as we use today (excluding the issues of electricity vs oil for vehicles, feedstock conversions, etc.).

    That is a heck of a lot of 2km (1.24 mile) diameter holes filled with Sodium (or NaCl?) in the ground... And unless we take over equatorial countries--those holes in the ground don't do very well in local winter conditions for extreme latitudes (poor sun position). From my own experience near SF California, I would need at least 2x the collector area to account for clouds and sun.

    We may be having a slight language issue here too... I think you are typing "ray" when we use "radius" here (not complaining--English is my only language and I am pretty poor at it).

    You also appear to be changing materials for your system too... From you website, you talk about table salt (NaCL) and the heat available during solidification... And here you are typing about Na -- metallic sodium and vaporization -- a very different set of issues and safety/environmental problems.

    To even address 1% of US, EU, or Asia's power needs, you would need to build something like 500 of these solar power stations each.

    Also, by simply changing from "salts" melting/solidifying, to pure Sodium vaporization -- that is a huge difference in problems too... Most substances only change their volumes a few percentage points on melting (for example, Sodium expands about 2.7% on melting). I have no idea for Sodium, but for any material vaporizing its volume expands (liquid to steam--water expands about 1,000x at standard temp and pressure). And if you pressurize water to keep the volume down, you don't get the energy storage of converting it to vapor...

    So, making steel (usually in a refectory material like ceramic?) on a large scale would not seem to be the same as dealing with liquid sodium and sodium vapor (under higher pressures and temperatures) given the very reactive nature of Sodium.

    I assume that almost anything can be done on a small scale (in fact, liquid sodium, liquid lead, molten salts cooling systems have been used for years in nuclear reactors)--but conversion to a large high pressure vapor phase sodium cycle seems a bit out there for large scale solar--let alone the single house home energy system that this website is mostly directed too...

    And there has been a project in California where a Solar Tower used liquid sodium as the heat transfer medium. I could see that using several types of materials (one for heat transfer, like Sodium) and another phase change substance like Molten Salts (going for solid to liquid--not to vapor phase) can also be interesting... And various demonstration projects abound using these, and other methods to collect power, have been around for years.

    http://en.wikipedia.org/wiki/Solar_thermal_energy (wiki is used only as a starting point)

    Overall, I don't think that these will revolutionize the collection of Solar energy overnight--however, as oil becomes more expensive to produce, other technologies (plus conservation) will slowly become available.

    Something to thing about is that very hot molten salt and/or sodium systems can be used to generate hydrogen gas directly (instead of from natural gas like is done today).

    Below is a link to a Spanish project using two solar fields about 512,000 sq Meters to run two 50 MW plants. They operate at 400C using synthetic oil, and a molten salt storage tanks for evening generation.

    http://www.solarpaces.org/ANDASOL.HTM

    Using their 170 GWh/year and 512,000 sqMeters (per plant), that works out to about 332 kWhrs/sqMeter per year or 909 watthrs per day. Using your number of 1,800-2,000 kWhr/sqMeter per year, that would be about 16.6-18% efficiency. Good, but not 25% conversion yet. And you still have the (very substantial) transmission and distribution losses to take into account too (building in hot/dry climates and sending power to population centers).

    Don't get me wrong, I would love to be proved wrong... But there is still a huge amount of work that needs to be done before we are getting much more than a small fraction of our power from Solar. Wishing it to happen will not make it happen.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: Energy independent housing

    I was talking about sodium utilization to transport the heat of the sun.
    It absorbs heat when it evaporates and releases heat when it becomes liquid,
    it practically transports heat.
    It would be able to transport a lot of heat from the sun to sodium chloride without problems.

    This big hole in the ground completely receives all solar radiation, it's not as some projects that use solar mirrors..that have high costs and forget a lot of sun on the ground...
    If three kmq produce 1 billion kwh of electric energy then this is the result:
    Spain would need a surface around only 600 kmq to produce all its electric production..
    Etc...






  • System2
    System2 Posts: 6,290 admin
    Re: Energy independent housing

    None of this will involve, nor have any impact on my home, in my lifetime.
    Solar; wind; hydro and conservation already has and will continue to.
    I would love to be proved wrong, but I know it aint gonna happen, not in my lifetime.
    Wayne
  • System2
    System2 Posts: 6,290 admin
    Re: Energy independent housing


    Well put Wayne.


    brad

  • System2
    System2 Posts: 6,290 admin
    Re: Energy independent housing

    "None of this will involve, nor have any impact on my home, in my lifetime. "


    You probably would have said the same thing about solar PV's 40 years ago.  Using that logic, I guess there's no sense in developing new technologies if they don't come to fruition by next year. 

    Bad Apple