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Everything posted by Prime-Evil

  1. LOL. It would be nice to see more small efficient heat pumps. I have thought of making one that would use inside stale and humid air as the heat source and using the heat to heat my hot water. It would depressurize my house slightly, but I would have cold air leaking in instead of warm air leaking out without any heat recovery. I have a semi-leaky house. The other think to do would be to keep making ice and tossing it outside, but by spring you would have a huge mountain of ice in your backyard. I suppose you could they bring it inside and use it for refrigeration and iar conditioning, but I think flooding would be a major concern. 160w Sanyo 500 BTU/h x 24h/day x 180 days / 150 BTU/lb = 7.2 Tons = 8 cubic meters of ice ! WHOA Betty is right.
  2. Hey Charles. Maybe we are related. We seem to share the same last name. Let's say you have an average monthly bill of $100/month and your cost is 10 cents per Kwh. Your average power use would be: $100 / ( 24h/d x 30.4d x $0.10/Kwh ) = 1.37 Kw. If you had a water turbine or a deseil generator running 24/7 driving a 90% efficient generator and you had additional losses on 50% of your power used averaging 90% for inverter losses to DC, 90% for charging losses to the battery, 80% on discharge losses from the battery, and you ran all your stuff off the battery as DC, then your water turbine would have to generate: 1.37Kw x 0.5/0.9 + 1.37kw x 0.5/(0.90x0.90x0.90x0.80) = 1.94 Kw More likely you would have 6 Kw running 8 hours a day. If you had a wind turbine, and you had enough batteries that your charging and discharging efficiencies were similar, but 100% of your power came off the batteries, and you had a wind regime and wind turbine performance curve such that you had a Capacity Factor of 0.30, then you would need a wind generator this big: 1.37kw / (0.90x0.90x0.90x0.80x0.30) = 7.83 Kw If you get all you power from the wind you would need an aweful lot of batteries, and sometimes they would be full and you would have to dump power. For this reason it is usually best to have a combination of wind turbine, generator, and perhaps a few solar panels also. Cost of all this offgrid stuff works out to perhaps $0.50/Kw life cycle, so to keep your energy costs within reason you really want to knock down your usage to the equivalent of perhaps only $40/month on grid. That would imply a combination of something as follows: Average Power: 550watts 25% Gas Generator = 1.6 Kw running 3 hours/day 50% Wind Turbine = 1.5 Kw running at 0.30 Capacity Factor 25% Solar Power = 800 watts perhaps at 0.25 Capacity Factor Perhaps 6000 Amp-hours of batteries. At times you would still likely have to dump power from the wind however, to a large hot water tank for example, so perhaps a 3 Kw Wind Turbine would be better so that you generate 500-1500w more regularly and dump the rest on the rare windy days when generation exceeds demand and storage capacity.
  3. Now what GrandMasterK needs to do is save up and buy his old man a heat pump, and have the AC side in his room and the heating side in the Old Man's room.
  4. Yeah. That's a much simpler way to explain it than my way.
  5. http://en.wikipedia.org/wiki/Earth%27s_energy_budget#Incoming_power Perhaps the best site I have found yet that supports Climate Change theory. Basically says solar radiation is by far the dominant energy source, and that changes in albedo have been more significant than changes in solar radiation, and that the Earth's albedo has been siginificantly changed by changes in land use and the burning of fossil fuels. I am still a little fuzzy on the effects of carbon dioxide levels on humidity. I am guessing that global warming increases humidity and humidity increases global warming. Yes? So it is essentially another positive feedback. Are we running out of negative feedback? My guess is that plants would normally grow more during an interglacial period but we have not let them, so we need to be planting trees like mad and letting them grow and not remove so much biomass from the forests but let it rot. Yes? Too late? No?
  6. I think you are on the right track if you need that much power and want constant power at near the optimal specific fuel consumption. Highest efficiency is usually found somewhere around the same rpm as maximum torque, but 1800rpm is probably the easiest if you want 60Hz, or 1500rpm if you want 50Hz. Diesels have really good low end torque so 1200rpm or 1000rpm might be even better. I am not sure what power you would get maximum efficiency, but if you lean more to the quiet side of that you will get longer life. A 1000/1200rpm 15kw generator seems about right. If you are using it for occassional emergency power and only need 3kw or so then you might go down to 500/600rpm and find a nice sweet spot. You should right to Nissan and get the performance curves from their dynamometer test. So what is the price of diesel and electricity in Bermuda? Just curious. If you had a 5kw wind turbine you could use it to produce hydrogen fuel when it is generating more power than you need and then run the desiel generator on hydrogen or hydrogen/desiel on days with no wind. I would imagine there are restrictions on such things in Bermuda. Really nice place though. Too bad about sea level rising and all that. Should be good for another 500 years or so eh. A good desiel engine should last that.
  7. Titration? Not as easy to measure in real time, but perhaps useful in experiments and for calibration purposes. http://en.wikipedia.org/wiki/Titration
  8. That's more or less what I was thinking. A 500w Heat Pump unit might produce 1500w of heating. Run in reverse at the same COP it would produce only 1000w of cooling, so I get a difference of 33%. Of course it also depends on whether it is located inside your house or out. Its hard to compare real data because everyone likes to work in funny units like TONS and stuff and its difficult to compare apples with apples when a system is designed and located primarily for one and not the other. The delta-T of course makes a difference also, but we are assuming that is the same. Depends on where you live of course. It is easier to heat in Florida obviously, and easier to cool in Nunavut.
  9. At higher temperatures (for higher efficiency) hydrogen engines will produce more NOx. This could be avoided by not having Nitrogen in the air, but it would be more practical to reduce efficiency somewhat to some happy compromise. At home you could run a hydrogen powered generator in a combined heat and power operation for your heat and hot water when the wind is not blowing.
  10. I have also read that hydrogen engines are capable of higher efficiencies. I suspect it has to do with the temperature of the exhaust being lower. I have also read that they produce less power for the same sized engine, but this would be a bonus if you wanted to convert an engine that you considered to be inefficient because it was overpowered to begine with. The storage of hydrogen is a problem, but less of a problem at low speeds and over short distances. A hydrogen car is potentially more efficient than an electric vehicle, unless the electric vehicle is connected to the grid, like an electric train or street car. Such a vehicle could then be powered from a combined heat and power source, or wind energy etc. An interesting idea would be to have a tank of compressed hydrogen which is refueled at home from your otherwise oversized wind turbine. The wind turbine could be 5kw and generate power for your home when generating 1kw or less, but produce hydrogen and store it into a tank when generating more than 1kw. In addition to your commuter having a small hydrogen tank refilled at home each night, it would have a compressed air tank which is resupplied by dynamic braking. In this way your engine would not have to do any compression, but would only have to do combustion and expansion. The exhaust gas would be cooler as a result also, for more efficiency. The engine would essentially be a steam engine, or perhaps something sort of half way between a steam engine and a diesel. Efficiency could easily be 25%, perhaps 40%, but considerably better than 15-20% of gas engines. Electrical cars are surprisingly inefficient due to the charging losses, discharging losses, inverter losses, and the losses associated with having to carry around all that extra payload. They are potentially very efficient for neighbourhood vehicles, but so are bicycles. They do have there place. There should be more of them.
  11. Norman, I like your approach. I think even in a relatively cold climate passive solar heating is very doable. Also I thing south facing vertical glass is the way to go for sure, especially if you have a nice view in that direction and can get reflection off of a snowy winter field or lake. Shutters are the way to go also. If you have less than 50% glazing on a wall it is easier to have practical shutter and if you have practical shutters you don't need as much glazing. Overheating is less of an issue also. Sounds like you did everything right. Hope it looks and feels right also. Buildings are for building. Dwellings are for living in. Have you built a solar hot water heater yet? I am working on one this summer. Not as practical for winter, but very practical for summer.
  12. I would rather be a free range chicken myself. Smaller dwelling are better though. It's interesting that 100 square feet on the water with a sail over it is considered a yacht, but anything on land under 2000 sqft is somehow unsuitable, even for a modern family of 1 person and a cat. Also, this buisness of mixing human feces with drinking water. What's up with that? Neat houses: http://tumbleweedhouses.com/houses.htm#roof
  13. I think you have to consider exergy analysis. Heating hot water should cost more than heating a room. If you use electric heat both cost the same, but heating a room with electric heat is arguably more wasteful because there are easier alterneative. For example, a heat pump can achieve a higher capacity factor heating a room to 70degF than water to 140degF. In general, air conditioning is more wasteful than heating because the energy you use adds to the problem, whereas with heating the energy you use running a motor and so forth at least helps accomplish your goal.
  14. It's a tribal thing. What is culture without diversity? It should be done by a doctor though, unless a witch doctors is available.
  15. All animal species have complex courtship rituals. More complex animal species have systems of taboos in addition to systems of rituals. My understanding of our characterization of sex without courtship as shallow is related to this. It's all part of the game, and its very difficult for us, even for the social biologists amongst us that study this sort of thing, to every really truly operate outside of our basic human nature. Of course as an engineer I can do it, but more as an involuntary form of birth control.
  16. Interesting thread. A lot of good suggestions that hadn't occured to me before. Here are some additional points: 1. We have hair. It is just very short, on most of use. 2. Is our apparent nakedness an evolution or an adaptation. That is, do we have the capacity within our genome to become hairy by adaptive selection without mutation and evolutionary selection? Some more theories on the advantages: 1. For some time we have been been carrion eaters, when hungry enough. By having less hair we are less likely to contract a disease. 2. From time to time we have been semi-aquatic, and having less fur makes it easier to be semi-aquatic under certain circumstances and non-aquatic under other circumstances. 3. For some time we have been very nomadic, able to range over incredible distances within our lifetimes and even farther within a few generations. First we evolved to be highly adaptable by being able to be more or less harry depending on the local climate. Of course this sort of adaptation takes time, but we could have evolved in such a way as to adapt within fewer generations. But by becoming naked we were able to adapt to different climates simply by using fire and wearing varying amounts of clothing. When we started using clothes, we more permamently adapted to be more versatile by having less hair regardless of geography and climate. 3. Perhaps the greatest advantage of being versatile for both hot and cold and semi-aquatic environments would be our ability to cross otherwise impenetrable geographical barriers, such as deserts, glaciers, and swamps. 4. Also, to be more versatile particularly in new surroundings and while covering vast distances, we can store a lot of fat under our skin. This has an insulating effect, which combined with our active brains and endurance means that we need to have less fur to compensate. 5. Combinations of all of the above. Some other questions might be: 1. How long have we worn clothing from time to time? 2. How long have we been semi-aquatic from time to time? 3. How far did individuals and tribes range 100,000 years ago, and beyond? 4. How long have we lived in both hot and cold climates within generations? 5. How long have we had the capability of being so incredibly fat?
  17. Ethically speaking, not my cup of tea, but I suppose if both parties were consensual, and had in fact the capacity to consent, or perhaps if neither part had legal capacity, for example if the human was mentally challenged or insane. What is the age of consent amongst other members of the great apes? Perhaps a future question for the Great Ape project. My guess is that most of the Great Apes know this is just plain wrong, except maybe those Bonobos. I'm told they're like a bunch of wild animals. http://www.greatapeproject.org/ http://images.google.ca/imgres?imgurl=http://www.paniscus.net/immag/HS_B03.jpg&imgrefurl=http://www.paniscus.net/immag1.htm&h=425&w=640&sz=31&tbnid=M595KG58n5oJ:&tbnh=89&tbnw=135&prev=/images%3Fq%3Dbonobo%26hl%3Den%26lr%3D&start=3&sa=X&oi=images&ct=image&cd=3
  18. You might just be being picky. Whether you call them rules or traits is interesting. Rules sort of implies deliberate intent, but it can also imply mechanisms with an apparent or perceived intent or systematic functionality. Traits are OK also. Somewhat more objective. Perhaps a little too lifeless. I suppose it depends on whether you are more of a biologist or a chemist. I am an engineer, so I am neither pretending to be both.
  19. But to answer part of your question when heat radiates away from the earth it does so to 'deep space', which is another way off saying all the matter out there that is colder than we are, but not the stuff that is warmer. We gain heat by day, and lose heat by night, in perfect balance, almost. Surfaces near the equator gain more heat, and surfaces near the poles lose more heat, and so heat is transported from the tropical regions to the polar regions through the tubulent mid-latitudes by ocean currents, and atmospheric currents, and weather. Again, all in perfect balance, almost. There are diurnal cycles, and annual cycles, and many other mechanisms and cycles and trends of larger and smaller and in between scale. It is very complex, but also quite robust, but not so robust that we can't mess with it. 6.5 Billion people, many of whom are children, tend to be a little difficult to manage sometimes.
  20. People should take a little inventory of where all the carbon is in the world. It's all pretty amazing really. All the cycles within cycles. We shouldn't try to oversimplify it. We shouldn't try to mess with it too much either, and the rate at which we are burning fossil fuels and deforestation is pretty amazing also, and quite significant. I don't buy the argument that humans are powerless against the forces of nature. For 5000 years such people have claimed dominion over all the Earth. It is a little late now with 6,500,000,000 people to deny accountability. By 2100 we might make up 1% of the total biomass on the planet. We are currently 0.3%. That is pretty significant for a species near the top of the food chain, even if we weren't all a bunch of self-destructive pyromaniacs. EDIT - I was mistaken. Humans are much less than 0.3% of the total biomass. We might perhaps be 0.3% of living land animals, but I really have not idea. It would be good to know though, and compare to historical levels. Thanks Herme3 for pointing out my mistake.
  21. You must first demonstrate to a woman that she is important enough that you are willing to sacrifice your principles and leave yourselve compromised and vulnerable. Lieing is the most direct and traditional way of doing this, but whatever works, works.
  22. Even the hybrids are overpowered fluff.
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