Sharing her years of experience freeze drying the foods we all need for surviving in times of scarcity, Katja’s knowledge and expertise will be invaluable to you, as you begin to freeze dry at home, preparing your own MREs for long term storage. Freeze drying for yourself provides significant savings compared to commercial freeze dried foods. And the quality of commercially available freeze dried foods and MREs does not begin to compare with your own. Katja will show the HarvestRight home freeze drier, share edible samples and explore the many options, accessories and techniques available. The presentation will include Q&A for the serious and the novice attendees interested in preserving nutritious food for up to 30 years.
This is the first ever air conditioner given the “Most Efficient” award by Energy Star – Energy Star finally got something right. This AC is about 35% more efficient than normal ACs due to the inverter technology, but look at the design!
The window literally closes right down the middle of the unit keeping the noisy compressor side on the other side of the window while only the quiet, cool air is on the inside. Its only a few dB louder than a library.
I just ordered one and am having it delivered to Home Depot since for some reason, through Amazon, it can’t be delivered go my home due to the location – never seen that before. In any case, this Midea company offers an 8000, 10000 and 12000 BTU unit.
Needless to say, you can still have full functionality of your window when you want unlike other AC’s where the are locked in the up position due to the fact that you simply have to have the window all the way open for the AC to stick through the opening but not with this one.
I have a portable AC that I stick in the window and use for maybe 2 months here in Spokane, Washington but it’s not cutting it now and that is why I was prompted to search for a better AC and was happy to have found this Midea U-Shaped Air Conditioner.
Check out the temperature here in the Inland Northwest – going to be 113F tomorrow and 100 minimum every day for the next week and unfortunately, that’s not Photoshopped!
A university project created a cooling system that creates about 600% more work than it takes to run the system using memory metal.
In this brief article, you’ll learn how something can easily produce way more work than it takes to run it and there are no violations of physics.
Electric heating element heaters are energy hogs for the heat they produce but regardless, they are 100% efficient already. And there is nothing magical or special about a 100% efficient heating system.
Why? Because nichrome or other heating element wire is thought to dissipate or waste all the electrical current that runs through it. That is not even close to being the reality, but that is what conventional science believes so we’ll just entertain that for the purposes of this article and to keep it simple. Normally, heat is considered waste in non-heat systems but if you power a heating element and it “wastes” all the electricity, then it is 100% efficient since the desired work is the heat.
Efficiency is a funny subject because as absolute as it sounds, it is really an objective measurement because efficiency changes depending on your perspective of what kind of work you want.
An incandescent bulb is considered 10% efficient since the desired work is light while 90% of the energy is “wasted” in heat. However, if we want to use those bulbs as heaters, then magically, they would be considered 90% efficient, with 10% wasted as light. But if you want some heat AND light, then the bulb is also magically considered 100% efficient since 100% of what you are using to power the bulb is creating both power and light.
Heat pumps create hundreds of percent more heat/cooling than the electricity required to run them – geothermal, refrigerators, air conditioners, air source heat pump dryers and water heaters, etc. yet, they are less efficient than heating element heaters.
Efficiency is a ratio of TOTAL input to TOTAL output. The heating element produces as much heat as the wattage is provided. It is 100% efficient.
But there is another measurement, COP or Coefficient of Performance, which is the ratio of ONLY WHAT WE PROVIDE on the input compared to the TOTAL output. With a heating element, we provide all the input so total output divided by our input will equal 1.0 or COP of 1.0.
With heat pumps, the story is very different. If it takes 200 watts of electricity to run a compressor to circulate a refrigerant through compressions and expansions cycles (that creates high and low potentials in the system), heat moves for free towards a colder area so the total amount of heat moved in a heat pump can easily be 300, 400, 500, or 600 watts worth of work in an electrical equivalent – for only paying 200 at the wall.
If you put in 200 but you get 600 watts of heat movement, the total desired work is 600 watts worth divided by only your input (not counting free environmental contribution) of 200 watts = 3.0 or COP of 3.0. That is a 300% NET GAIN in total energy (work) produced compared to what you have to pay for. But if you look at all input including environmental input, it will be under 100% since there are losses. That is how you can have a system that produced hundreds of percent more work compared to what you pay for although it will still be 100% efficient of less.
The cooling system methodology created by a team led by Professors Stefan Seelecke and Andreas Schütze at Saarland University is technically not new in concept, but it is the best example of taking advantage of an interesting memory metal called Nitinol and it’s known effects of soaking up heat while it gets bent and releasing the heat when it straightens out.
The cooling system is made of a cylindrical chamber with a rotor that has nitinol metal strings running along the length. There is a cam system that flexes the wire as it rotates for 1/2 the revolution. During this 1/2, the wires soak up heat in that compartment, which cools the compartment down. When the wires goes into the other side of the chamber, they are allowed to straighten up and they release a lot of heat, which heats up that compartment.
There is air moving through the devices to move both the hot and cold air. The claims from the university is that it is about twice as efficient as a heat pump. As you know from the examples above that a heat pump could have a COP of 2.0 or 3.0 easily. That means that this new Nitinol cooling device would have a COP of 4.0-6.0 or 400-600% more work done than the motor takes to rotate the cylinder!
A group of students from the University of Calgary have developed a simple evaporative refrigerator. It was inspired by the way that animals and insects keep themselves cool.
Warm air from the surroundings is funneled into a pipe network to evaporate water moisture, which carries heat away from the air. Once the air is cooled, it moves into the chamber where the food is kept. The only power requirement to bring the temperature down to 4C is to power a small fan to move this cool air, which can be done with a very small battery setup powered by a small solar panel. The refrigerator still works with no electricity but works best with the fan.