Putting the best possible light on it, it is a human powered machine designed to match the natural ways our bodies move. So it won't be producing more than the 1/10 horsepower I mentioned earlier. It won't reduce expendable energy usage (at least here in the US) because that oil will come in the form of food. 1 Calorie of food requires up to 10 Calories of fossil fuel input, so any American-human powered machine is at best 10% efficient. Nor will it solve unemployment. If anyone was willing to pay a living wage for humans to convert food into energy of motion, they would already be doing it. In order to out-compete gasoline, one would only be able to pay $0.07 per day. Even most depressed countries are doing better than that.
USDA says: "The zones in this edition were calculated based on 1976-2005 temperature data. Each zone represents the average annual extreme minimum temperature for an area, reflecting the temperatures recorded for each of the years 1976-2005. This does not represent the coldest it has ever been or ever will be in an area, but it reflects the average lowest winter temperature for a given geographic area for this time period. This average value became the standard for zones in the 1960s."
So the only information going into the maps is minimum temperature. Data is also only fine down to a square 1/2 mile on a side. I suspect that I have at least two zones on my property, possibly three. If you are determined to have almonds, and willing to put in some effort, and have a few failures, I expect you could grow them.
You assume a COP of one, yes? How about spinning a heavy flywheel to even out output and gearing it to run a heat pump compressor? Shouldn't it be possible to cut the time to less than half your estimate? Maybe use one side to cool a cold pack to take with my lunch and the other side to heat my coffee, both with less time than many people devote to a morning exercise routine and no need for grid power.
Yes. If you have seen a heat pump small enough to be hand cranked and produce a cup of heated water, I would be fascinated to see it. No need for the flywheel, compressors work fine with slight variations in input.
If we are going to try to avoid grid power at all costs, we should really calculate what that cost is. How much money, energy, pollution, etc. are caused by the food you need to eat to pedal the bike to make your coffee? US food production and distribution make electricity production and distribution look efficient.
Annie Hope wrote:As we mentioned last year in this post, https://permies.com/t/28774/labs/Solar-Voltswagon#296072, we have 12 X 800amp 2v sealed deep-cycle batteries, which are about 50kg each. We bought them to go into a food trailer, but have had local "expert" (who also runs the market where we will use the cart - so it pays to keep on side with him) keep trying to convince us what a bad idea this is, and that we need to keep them at home as part of a home solar power system. Previous advise was that it would be dangerous in terms of fumes, and explosion risk, and to put them behind concrete. Now we are also told that he thinks that regularly moving deep cycles batteries is bad for them and would shorten their life. Is there any truth in this? I mean they run golf carts etc all the time. We would be taking them slowly 2-3km (1.5 miles) to the local market down a flat country road, and then home again.
I have never heard that moving deep cycle batteries in any way injures them. That said, I certainly wouldn't move 300kg of batteries unless I absolutely needed to. That is a lot of weight, and a lot of energy to move that weight. Fumes and explosion risk are small, and generally an issue when charging batteries. Most commercial charge controllers make this a pretty small risk. Have you done a energy use analysis to determine how much energy you need at the market. I can't help but think that those batteries are way overkill.
We are currently thinking of leaving 6 at home, and taking 6 with us (so 300kg each). We could have them fitted into the food caravan, or we could put them in the back of our van for now (this vehicle is used almost solely for towing the food trailer) and have a little trailer made when we can afford it, and tow them separately (we could use our little 800cc Suzuki Alto for this probably) and we could then also pull them round the farm on a quad bike or ride-on when we can afford one.
They have also been sitting uncharged for over a year in storage, but we are getting them delivered here this week. (they have been used before we got them). How much damage could this have done? Is it best to recharge them ASAP? They are currently sit up in parrallel to make 12V. Could we put a normal 12V car charger on them and (VERY) slowly charge them from normal grid power? Could we also then just put a 2000W inverter that we have on them and use them that way till we can afford.
Best to charge them ASAP. Assuming we are talking about lead-acid batteries here, they generally want to be fully charged as much of the time as possible, and never left discharged. An inverter is used to make AC from DC, both solar systems and batteries work on DC. Solar with a good charge controller would be where I started.
mark andrews wrote:My 2 acre forest garden is in it's first year.
I brought in 600,000 lbs of wood chips and have about 300 new trees/shrubs that are going to make it.
That's a LOT of wood chips! I figure that is 4" deep over the entire plot. Wow.
There are no grasses at the moment--just lots of wood chips.
I have one chance to plant the right thing that would be great for chickens when I introduce them next year, but not something that will compete with tree/shrub/veggie roots like our local bermuda will.
I won't be planning on mowing the grass and I won't be ready to introduce anything like a sheep until the system is much more mature.
I am in southern New Mexico.
Are there any grasses that don't have invasive root systems that would be great for chickens.
Three suggestions I would have:
1) Talk to local farmers about pasture mixes for your climate. A mixture is almost always going to be better than a mono-crop.
2) Try annuals (grasses or otherwise).
3) Start some nitrogen fixers right off the bat, clovers, peas, beans, vetch, etc.
Also check out the video here about chickens fed solely on compost piles (aka 600,000 lbs of wood chips).
Jenna Sanders wrote:If I'm recalling correctly, some of the foxfire books have information about planting during different moon phases...it would take some research, but this would be an excellent resource to have!
I have never understood this. A moon cycle is 29 days, say I am supposed to plant during a full moon, I might be planting 29 days later one year than another. In Maine that can be half the growing season (just kidding, sort of). Even if there were some advantage to planting on a full moon, I would be better off planting sooner, and having slightly less good plants, with 4 weeks more growth.
Troy Rhodes wrote:I purchased a BayGen radio b/c I liked the concept so much. THat's a radio where you wind a spring and that runs the radio for ~ 30 minutes. It was a big bulky box for essentially a tiny am/fm radio, just because of the spring. It cost over a hundred bucks, just because of the spring/engineering. Warnings all over the place to -NEVER- open the radio due to safety concerns about the spring.
On the other hand I have an emergency radio with both a crank generator, and a small solar panel. It also runs for about 30 minutes after I wind it, or all day if in the sun. It contains a small battery and some capacitors. I think it cost about $40. Just another data point.
Matt Powers wrote:Would you say water is potential energy because water is rarely "still"? Water is always moving, even when frozen.
I wouldn't, since I would not be trying to be 100% technically correct at the expense of being understandable to 4-12 graders. While I loathe telling kids incorrect things, I don't feel the need to be confusing by adding unhelpful exactitude. You didn't say 'air' for instance, you said 'wind'.
Alder Burns wrote:You are asking this question just in the nick of time for an easy, fun observation that a lot of people don't know about. The full Moon tracks the same path through the sky as the sun does six months later. And tonight is the full Moon! So if the sky is clear, just go out and look....the light and shadows cast by the moon through the night will be like the sun will cast in early January.......
Great observational tool. Note that the moon can be in any phase, it is just easier for a full moon.
And, of course, there is an app(s) for that, if you have a tablet or smart phone.
If you end up thinking about a pre-98 Subaru Wagon make sure to check out the rear wheel wells. That is where my '96 rusted out. It was a common complaint with them around here (in snow and salt country). I also had problems with the starter when I sold it. But it lasted 220k miles, and I loved it. Now I have a used Prius that get twice the mileage, and holds far more that one would expect.
I pay for my water, and I assume most other people do as well.
If an invention requires new laws of physics in order to work, people are justified in making the case that the prize money from the Nobel prize should be used to capitalize it.
Conservation of energy requires that no more energy can be achieved by putting the water back together, than was put into it to break it up.
The efficiency of an internal combustion engine can be increased even by using several energy conversion methods, all of which are less than 100% efficient. One only needs to drive a hybrid to see this in action.
The way to test the efficiency of a new engine technology is to run careful experiments on a dynometer, not to install it in customers cars, and hope the placebo effect works for cars.
Bill Bianchi wrote:And, a fan is as efficient a room heater as a standard electric heater? Mine just make me feel cool when they blow air on me.
This is evaporative cooling for you. It cools you at the expense of heating, and increasing the humidity in the room. The sweat on your skin evaporates more readily in a breeze, and takes 970 BTUs of heat (per pound) to make the transition from liquid to gas. That heat comes from you, making you cooler.
Bill Bianchi wrote:I seriously doubt a converted fan will be anywhere near as efficient or energy saving as a portable heater.
Why? Where is that energy going if not into heat?
A converted fan is almost exactly as efficient as an unconverted one, which is almost exactly as efficient as any other electric heater. Or computer, fax machine,...
A fan increases the speed of air molecules, which if there are confined to the building, just means that the temperature of that air went up. How much? By the watts consumed by the fan (minus the heat that the fan puts into the housing etc., which also eventually probably end up in the air). Thus a fan is an extremely efficient heater.
[note: whether the converted fan draws more power is probably dependent on the particular design of the fan electronics.]
Bill Bianchi wrote:If I have these replies straight, a greenhouse gets hot enough in the summer to kill crops if not well ventilated, but not hot enough to heat water for home use, even if I use black barrels and put reflective material on the back wall to reflect more sunlight onto the black barrels.
I wouldn't go that far. A black bag full of water on the lawn, will get you shower-hot water. The issue with the greenhouse is that you are heating a large space to a temperature where it isn't useful for anything else, just to get a bit more heat into the hot water system.
During winter months, it's not going to be warm enough to heat air for home heating due to poor insulation. I assume putting a more traditional hot air heater inside the greenhouse wouldn't improve the performance of that solar heater, either.
A greenhouse certainly will heat air for home heating. The question is how much, and are there better ways of doing that.
Bill Bianchi wrote:Heating water during summer months in barrels inside the greenhouse seems doable, in theory. The advantage I think I see is the ability to heat a larger volume of water, which would be advantageous for a large family---7 family members in my home. Ideally, I'd like to shut my hot water heater off during the summer and draw from a large reserve of solar heated water, instead. Possible? Don't know.
Possible. The barrels will need to be insulated from the environment. The usual way to do this is called a batch heater, a black barrel inside a glass topped enclosure. Heat the water, then draw hot water out of it as needed. A greenhouse isn't much help in this configuration, too large, too much surface to be insulated. Temperatures in the tanks want to be in the 150°F range. I heat my own water with solar panels, and easily get around 8,000 degree-gallons on a sunny day (from 128 square feet of collectors), call it 60 degree-gallons/foot^2.
As for an air heater during winter months, I just don't know if that would work. Maybe not. There is a greater volume of air in a greenhouse, but if most of it is lost due to poor insulation in the greenhouse, then that use is probably not going to work. Just exploring ideas at this time. Fully aware both uses of a greenhouse may not work very well.
Air heaters for the winter are better optimized with small volumes for a given area of solar-intercept. Properly done you can get a substantial amount of heat out one.
I recommend that people decide whether they want a greenhouse (i.e. a place to keep plants warm), OR a solar heating system. Both can work, but trying to combine them leads to failure (in my climate anyway). For a greenhouse, one wants thermal mass storage, and high insulation levels. For a solar heater, low thermal mass and insulation levels, and high heat transfer to the house. A greenhouse will provide *some* heat during the winter, but pulling too much will nullify its other purpose.
Logan Jonker wrote:I've seen in other posts, that a barrel of water in a greenhouse (or more than 1 barrel) would help slow the swing of temperature from day to night. Would this be useful in incorporating barrels of water into walls, tables, etc. in a home to maintain heating/cooling needs?
For continuously occupied interior spaces, increasing thermal mass helps with both heating and cooling needs. Combine that with access to solar radiation, and you can heat with free energy.
Would stacking 3 55 gallon water barrels, coated by 2 or more inches on concrete, would it offer structural support like in a wofati type structure. I know this would weigh over 700 pounds, but might cost less then 20 dollars a column, especially if non insulator mix of papercrete was used to cover the column.
I would talk to an engineer before using anything innovative as a structural element.
Further, what would the heat exchange properties be with a house full of these columns. Could this be safe/useful for passive heating and cooling?
For thermal mass properties, I would either use just the water filled columns, OR concrete columns. The advantage of water is that convective currents even out the heat transfer throughout the volume, encasing it in slow heating concrete would negate that advantage. Further encasing barrels in concrete would hide any potential problems with water leakage until they became actual problems. Leave water containers where they can be monitored, would be my recommendation.
As to thermal properties, water contains 1 BTU per pound per degree Fahrenheit (8.3 BTUs per gallon per degree F, 62.1 per cubic foot per degree F). Take the range of temperature difference that you are willing to tolerate, multiply that by the BTUs per degree F, to get total BTUs that can be used to moderate temperatures. For example, for 700 pounds of water, and an acceptable range of 61 to 70 degrees, you would have 7000 BTUs to pay with. Given a diurnal cycle, this would work out to around 10 gallons of heating oil per year savings (700 pounds * 1 BTU/lb-°F * 10°F * 200 heating days/year = 1.4 MBTUs/year Heating oil contains roughly 140,000 per gallon.) Careful engineering is required to actually achieve this level of performance!
[note: a 55 gallon drum full of water weighs in at 450 pounds or so.]
Picture 3 seems to disagree with the initial drawings concerning the North side connections, but seems to make more sense to me now. I couldn't figure out how you were going to raise that North panel (keys words, by hand to here). Still confused about where the roof panels sits (flat or slight angled)?
For preventing erosion, right now, I would use grass. Contractor mix is heavily biased towards fast growers, as that is their primary concern, looking good and not washing out. Get it down now, and water it once a day until it germinates. For the longer term I would mix in perennial clover and try to find other densely rooted stuff.
Andrew Parker wrote:An oversimplification aimed at converting highly trained professional soldiers into Peace Corp workers. Correlation is not causation.
Sure it's a waste of people who are trained to kill and be killed, but what the heck.
Correlation does not imply causation. But all caused things are correlated. And really who cares? If all that happens is that desertification is halted and reversed, or insurgency is reduced, I am happy with either outcome. And I am willing to suffer the penalty of not having as many dead people, for that end.
Timer frames are engineered with the braces in mind. I have seen buildings where they were removed, which induced failures in the structure, not with cob admittedly. Generally braces work in tension (at least some of the time), I have little confidence in the tensile strength of a cob to wood joint.
Why would you want to remove the braces anyway, they make the frame beautiful.