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Efficiency contest

Disclaimer: I may be biased, since I have an entry in the running.I am very confused as to why the current leaders of the efficiency contest are in the contest at all, nevermind winning.One is not instructions for making anything. It just says "watch less TV". It may be good advice, but it is not a DIY project.One is a recipe for bread. It may be wonderful and delicious bread, but it has nothing to do with being green.One is about making a suit out of a sleeping bag. I suppose this would allow you to turn down the heat, but that is a bit of a stretch, (besides, so would a sweater - and the instructable doesn't say anything about this being the reasoning).I don't mean to disrespect these fine instructables, I am just saying they are totally irrelevant to this specific contest.But not only are they in the contest, they have been in 1st, 2nd and 3rd place since voting opened 2 days ago. Who is voting for these entries, and why?

Topic by JacobAziza    |  last reply



Efficient LED lighting? Answered

I want to power 3x 0.5W LEDs in series with 3x AA Ni-Mh batteries (input voltage will range from 2.5 to- 3.7 ). The total forward voltage is around 10volts, and the current of the LEDs is 150mA. I've tried using a Joule thief but it's quite inefficient, even with different transistor / toroid / resistor configurations (even with fast switching Darlington transistors) the maximum current I've been able to get at the LEDs is less than 100mA, and many energy gets lost in the process, it seems the resistor between the coil and the base of the transistor slows down the switching process and limits the current. I need a more efficient way to power the LED's, either an improved design or a LED driver chip. But trying to keep the efficiency rate around 60-70% or more. I have found a design that claims to be more efficient (see picture), but I'm not sure about if it will deliver 150mA.

Question by Victor805    |  last reply


Potato cannon efficiency? Answered

I created a potato cannon that only has straight pieces of PVC.I have seen other designs where the combustion chamber is wrapped around 180 degrees with two elbow pieces thus making the cannon more compact.  Does anyone know which design is more efficient as in terms of launch power and speed?

Question by bobert610    |  last reply


How to increase efficiency in generator ?

I tried making generator with cealing fan. I found that the coil interaction with the magnetic flux is less and it is generating only 5v AC so i removed the coil and tried replacing the coil with the thicker coil.Can we increase generator output by increasing the coil thickness.Does the output of generator depends on the no of turns of coil or thickness.what should i do to increase efficiency of the generator.

Question by Shashank Reddy    |  last reply


Most efficient CO2 sensor?

I found this CO2 sensor. http://www.robotshop.com/parallax-co2-gas-sensor-module-2.html Any one know of a better one?

Topic by hthnc-student    |  last reply


A More efficient joule thief Answered

I need to make a joule thief type of thing that can up the power from a 0.55V source to a simple LED. I know that the joule thief is not the most efficient circuit which is why I am asking if you know of an efficient circuit I can use.

Question by physics_dude    |  last reply


Efficiency of DIY bitcoin miners?

First, I would like to say that I do not know if this is the place for this question, but: I have just heard of bitcoin mining and started to look into it.  I have learned that pretty much the only way it is plausible is through the use of a machine dedicated to mining the bitcoins, not through using gpu's anymore apparently.  But I have seen that these machines are expensive, so naturally I would want to build a DIY one if I started this.  But are these dedicated miners even efficient? And what if they don't have the top of the line components?  I tried to look this up myself but I don't really understand the hash rates of these machines so I don't know what is considered an efficient rate.  And, in my current situation, I don't pay for electricity or internet so now would be an optimal time to do so and maximize profitability.  So, do these dedicated miners work efficiently enough to make it worth while to build/buy one? Especially if I don't pay for electricity or internet?

Question by texpert    |  last reply


Solar Thermal Design and efficiency?

I have finished building and testing my diy solar thermal collector. i decided to paint the outside framework black, will this make a difference? also i was wondering how to work out the efficiency and power it can produce? the temperature difference was 17 deg going in and 29 going out at a flow rate of .36 litres a minute and the solar radiation was 800 watts per m^2. the temp difference might seem low and there a 2 reasons for this. 1)im in ireland and 2)i never bled the radiator so i have a feeling the water only flew across the bottom rather than circulate. Thanks

Question by rich5007    |  last reply


Energy Efficient Dog Door

Winter is coming and I have four dogs and two cats. We installed a dog door to the outside some time ago, but it's a big air leak. Even though we replace the door every six months, it's only plastic with magnets on the edges, and doesn't always fall back into place. I've tried various solutions, but what I really need is a solid door that locks into place, or a door that opens and closes with a trigger. Automatic dog doors cost about $350.00 - $450.00, and require the dog wears a special collar. I'm not looking for security, I'm looking for energy efficiency. Can someone please help? I know there are lots of others in the same position.

Topic by mattyw21    |  last reply


High efficiency coilgun design

Hello there I need some (a lot of) help with my project. I've started to design a high efficiency multistage coilgun. The main feature of the design is using the self-inductance formed in coils that were shut down for accelerating the following coils. To perform this, we can divide each coil into 3 segments (lets call them subcoils), connected with a wire and power all them 3 with a single capacitor. At first, the current from the capacitor is flowing through all 3 segments and a projectile is being pushed through the first segment. Than the first sensor is being activated with the projectile and it switches the power flow to only second and third subcolis As the current in the first subcoil is changed, the self-inductance directed in the opposite direction is appearing. In theory, we can use this power to increase the current in the following segments. The same thing is happening between second and third segments. And I want to place 3 of this stages (9 subcoils in total) I will use 8mm caliber projectiles, 40mm or 50mm length. I chose 5200mkF 450V or 6800mkF 400V capacitors, 2 of them in parallel for every stage (6 capacitors in total) Yes, I know it sounds way too powerful, but that's my actual goal. It's not my own idea. I have learned it from here http://gauss2k.narod.ru/adf/gs3seg.htm (русские вперёд). So, some problems had appeared. I can't figure out how to properly calculate the required inductance of the coils. In the source it is said that the inductance of the first subcoil should be equal to two of the second and the third subcoils (L1=2*L2=2*L3) to achieve the best performance. Also, my rough estimates show that peak current through the coil will be about 1,5-2,0kA for 3,0-4,5ms. This is quite a lot! I'll have to manage this energy and choose the power switches rightly. To sum up, I will be glad to hear your opinions about this idea. It's kind of controversial, but I hope it's not a certain failure.

Topic by CosmoKnight    |  last reply


Household Appliance Efficiency (Slowing the meter)

Hello, Does anyone have an idea how I can build a device or circuit board that I can hook up a computer  to monitor the efficiency of Appliance and hopefully write a computer programe to maximize the efficiency of the appliance and minimize the power drawn from the power grid. Basically slowing down the meter while the appliances still operate at their full potential? Thanks 

Topic by derf1973    |  last reply


Efficient/High output Joule Thief?

Right now, I am looking for schematics for the most efficient (1 cell and 1 LED) joule thief, to use as a durable reading light. I right now favour Quantstuff's 2 transistor SJT (http://quantsuff.com/LED2.htm) but I am not sure whether it is the most efficient. I've seen several others, but since they all claim to be equally as efficient, i'll have to rely on the experience of other tinkerers and hobbyists. So: what's the most efficient or high current or high voltage joule thief you know of?                                                                                                                          Thanks.

Question by .Unknown.    |  last reply


Efficient House in Maine has no Furnace

This house in Maine has no furnace and will generate more power than it uses. With some extreme air-tightness and solar panels this is one super efficient house. It even has mood ring-style lights on the side to let you know how it's doing. Green is for Net-Zero use, yellow is on the border, and red for pulling more from the grid. Linkvia MAKE

Topic by fungus amungus    |  last reply


¿What power source is more efficient?

For a project I have to decide between a mechanical generator (I.E. one attached to a bike's wheel) o an array of cheap solar panels.Anyone has experience with this? What is your advice?I only need to supply power to recharge four generic AA batteries once a day.Thanks!

Question by Daniel FranciscoD1    |  last reply


A more efficient way to stamp paint

Hi all! I have been working on a crowd source campaign for elaborately designed dice for a while now and have a problem with my home manufacturing process...hopefully, someone can give me some ideas. I need to find a quick and efficient way to apply paint to the raised surfaces of the dice faces. You can see in the rendered pic the 3d printed file that I'll be making the mold from. I made the numbers extend out instead of going in to simplify the painting but need to get down a system of applying the paint. I was thinking some sort of stamping but thought that was only good with ink. Any input is appreciated...

Topic by dmenegon    |  last reply


CHALLENGE 60% efficient solar build

I would really love to see this Instructable be done but i don't have the technical background or resources to do so. It seems like a pretty easy build and looks like it can be done with common items. If the project is done correctly it should be a very powerful source of energy for free. It converts solar energy at 60% efficiency which is almost twice as much as current solar panels. It works by converting solar heat into electricity by heating hydride (which is hard to find but i think it can be replaced with a refridgerant) into a gas, which generates pressure to run a motor which runs a generator producing electricity and then the gas is converted back into the liquid state. The project will replicate Solar Powered Electric Generator Please contribute the time to building this it will pay off tons. Thanks To Everyone Who Helps.Mark

Topic by BTBAMYEAH    |  last reply


If LED lights bulbs are so efficient, then why do they have cooling fins? Answered

Most of the LED bulbs now sold as incandescent replacements have cooling heat sinks on them. If they have such great efficiency, I would expect minimal waste heat with no heat sink needed. Do they get too hot to touch as well?

Question by LongToe    |  last reply


if we design solar water heater by two paralel cover glasses. what is the function of the outermost glasses? ?

What is the best range between two glass covers (in mm)? how to calculate the efficiency of this SWH? this swh is length, width, height 137 cm, 126 cm, and 10 cm. thanks for the answers

Question by diaz.zahara    |  last reply


Will removing a rear seat move the centre of gravity in a minivan too far forward? Answered

A family member frequently drives around in the van all by themselves, which I'm sure is an enormous waste of gasoline. Removing one or both of the rear seats will help reduce the weight of the vehicle and improve the efficiency a tiny bit. That said, I was wondering if doing that would cause handling issues due to the centre of gravity being farther forward. Also, winter is long and icy here, so rear traction is an issue 5 months of the year.

Question by zalf    |  last reply


How to get 9 volt from a computer power supply? Answered

To save some energy i thought it would make sense to remove all those small powersupplys. They all transform pricey power (24 eurocents per kw/h here) into heat. However, in my computer is a powersupply that actually is very efficient, also, if i take more energy from it, it wouldn't have much more loss. Right now my computer uses about 54 watts if idle (i selected the components to be as efficient as possible). My DSL-Router uses 14 watts, but i guess most of it goes away as heat in it's own little PSU. The DSL-Router needs 12 volt and my computers PSU can deliver that, and since the DSL-Router is only needed when the computer is switched on i plan to use the computers PSU to power it. I have a pair of speakers with an internal PSU and AMP. After opening them i saw that both are on separated boards. The PSU gives 9 volt to the AMP and gets quite hot while doing it. The problem: as far as i know there is no 9 volt power connection in the computers PSU :(.

Question by tecneeq    |  last reply


How do I figure out the cost differential between turning on an inefficient furnace and using oil-filled space heaters? Answered

The big deal is that this furnace also heats the upstairs unit of a duplex, which i also own and rent out to my brother in law.  the deal is that he spends maybe 5 nights per week at his girlfriend's house.  so, if i turn on the furnace, all of the heat that goes upstairs will be wasted.  i'm interested in learning how to measure energy usage and learning how to determine the usage difference between running the furnace, which is about 50 years old and runs at about 50% efficiency and three pretty standard 7-fin oil-filled space heaters.  the flat in which i live is about 800 sq.ft. and the upstairs space is about 600 sq.ft.  the windows are old, but are covered with plastic shrink film for better insulation.

Question by hobbssamuelj    |  last reply


Study: Ethanol Worse for Climate Than Gasoline

Ethanol is under fire again: At first blush, biofuels such as corn ethanol and soybean diesel seem like they would be great from the standpoint of global warming. The crops soak up carbon dioxide from the atmosphere as they grow, and that balances out the carbon dioxide they produce when they're burned. But until now, nobody has fully analyzed all the ripple effects of this industry. And Tim Searchinger, a visiting scholar at Princeton University, says those effects turn out to be huge. "The simplest explanation is that when we divert our corn or soybeans to fuel, if people around the world are going to continue to eat the same amount that they're already eating, you have to replace that food somewhere else," Searchinger says.Searchinger and his colleagues looked globally to figure out where the new cropland is coming from, as American farmers produce fuel crops where they used to grow food. The answer is that biofuel production here is driving agriculture to expand in other parts of the world."That's done in a significant part by burning down forests, plowing up grasslands. That releases a great deal of carbon dioxide," Searchinger says.In fact, Searchinger's group's study, published online by Science magazine, shows those actions end up releasing huge amounts of carbon dioxide. The study finds that over a 30-year span, biofuels end up contributing twice as much carbon dioxide to the air as that amount of gasoline would, when you add in the global effects. The rest of the article (and radio broadcast) is here

Topic by Goodhart    |  last reply


Green car mod roundup

Treehugger has a nice roundup of mods that people have made to their cars to make them more efficient or run on alternative fuels. They even included the Honda Accord that runs on trash in the list, which is pretty cool. Other mods include wood-burning cars, biodiesels, wood-burners, solar-power, hydrogen, and aerodynamic enhancements. Check out the link for the slideshow. Note: there are 17 slides, not 17 cars. 17 DIY Cars Hacked for Fuel Efficiency

Topic by fungus amungus    |  last reply


selective room heating?

I just turned on the heat before going into my room to go to bed. My roommate and I are in about one fourth of the whole house (and will be for about six hours), yet every room is being heated. This seems like a huge efficiency problem. Are there commercial systems out there that can heat selective rooms? If not, are there ways of making such a system? Can I just tape cardboard over the vents?

Topic by moisture    |  last reply


Audio: 8 hours of Amory Lovins lectures

Video with slides http://www.rmi.org/sitepages/pid231.phpmp3 audio only http://sic.conversationsnetwork.org/series/si-energy.htmlAmory Lovins runs the Rocky Mountain Institute, working on cars made from thermoplastic/carbon re-formable body panels among other projects.He's a charismatic motivational speaker on the subject of energy solutions. Listen to this stuff to get enthused again after you get burned out by hearing about what our idiocracy is doing to us and the world. It's a really it's nice to hear him saying that thetechnology solutions exist and all our dreams will come true once we switch tothem. And this crisis is just the thing to get us off the dumb old methods thatare only used from habit.

Topic by TimAnderson    |  last reply


LDR and/or PWM for energy efficient 'smart' dimmer?

Is there any way to combine a Light Dependent Resistor or other light sensor with a Pulse width modulator to (energy efficiently) dim indoor lighting in the presence of sufficient natural light?  Thanks!

Question by bbawco2    |  last reply


What is the most efficient way to transfer motion? Answered

What is the most efficient way to transfer lateral movement to vertical movement via a ramp. The following curve is equal on both sides of the apex, if that is the correct term.  Is this the best way to transfer the movement to strait vertical or should something else such as a long start to the incline and then a sudden shoot up.

Question by jj.inc    |  last reply


World's most efficient solar dish? - MIT

A team led by Massachusetts Institute of Technology students last week successfully tested a prototype of what it says may be the "most cost-efficient solar-power system in the world," revolutionizing global energy production.The 12-foot-wide dish, made of a lightweight frame of thin aluminum tubing and mirror strips, concentrates sunlight by a factor of 1,000, according to the Cambridge, Mass., university. It can create heat intense enough to melt a bar of steel. More from ZDNet

Topic by Goodhart    |  last reply


dc-dc Buck vs boost efficiency

Hi guys. When you  use solar panels and have gadgets with different voltage requirements  that you want to power up. I need atleast  2 different outputs, 5v and 12v  ,   so which is most efficient ,  12/15v panels that you  regulate to 5v , or  5v panels boosted  to 12v? is there any general advantage in either case and i,m talking about using  cheap ebay switch regulators / boost converters,  not anything expensive hi tech. regards

Topic by kristerh    |  last reply


More efficient bike charger for USB devices?

I' been inspired by these bike lights from reelight.com. I have a set of these for my bicycle for reliable and very effective lighting. It's stated they are powered by "pure induction". There's got to be a way to harness the energy from both wheels to charge a USB device (5 volt) in the same manner. Instead of using a friction generation mechanism bike charger or bike generator.Any thoughts?

Question by rhow    |  last reply


efficiency while charging through solar cell.

we know that solar panel gives maximum power at particular voltage.which is a bit less then the actual rating of the panel. my aim is to get a constant voltage across the battery,okh. but can i do sth by which i can get such const voltage 4 which the power provided by by solar cell is maximum. i can introduce a microcontroller which will continuously check the voltage ......and itwill get stuck at dt particular voltage...but i am getting puzzled with dat,ne idea plz

Question by sumgupta89    |  last reply


HHO generator improves fuel efficiency of petrol engine!

Reproduced verbatim from The Fortean Times issue 249, republishing from FT35JUNE 1979On the 15th a demonstration of a "revolutionary" energy device took place at an undisclosed location in the UK. Iowerth Thomas, 58 a Welsh inventor, hoped to interest both government energy officials and an Arab consortium. Mr Thomas had been experimenting since 1936 with ways to make petrol engines burn more efficiently. His "bolt-on" device promised between 25 and 40 per cent efficiency using "the electrolysis of tap water", plus a cleaner exhaust. The government scientists' response - that it was impossible - spurred Mr Thomas to demonstrate it for them. He reported to the motoring correspondent of the Daily Telegraph that his stationary engine ran for 112 seconds with his device and for 77 seconds on the same amount of petrol without it. The usual objection to electrolytic systems is that the energy needed to run them is greater than that produced. With some sarcasm, New Scientist sniffed that the device needed to be much smaller than the room-size contraption Jones used. What really stoked their scorn was Thomas's reply when asked how it worked: "It's beyond me," he said. That was the last we heard of him and his promising device.How has this technology improved in the last 30 years?L

Topic by lemonie    |  last reply


Sandia, Stirling Energy Systems set new world record for solar-to-grid conversion efficiency

31.25 percent efficiency rate topples 1984 recordALBUQUERQUE, N.M. --On a perfect New Mexico winter day -- with the sky almost 10 percent brighter than usual -- Sandia National Laboratories and Stirling Energy Systems (SES) set a new solar-to-grid system conversion efficiency record by achieving a 31.25 percent net efficiency rate. The old 1984 record of 29.4 percent was toppled Jan. 31 on SES's "Serial #3" solar dish Stirling system at Sandia's National Solar Thermal Test Facility.The conversion efficiency is calculated by measuring the net energy delivered to the grid and dividing it by the solar energy hitting the dish mirrors. Auxiliary loads, such as water pumps, computers and tracking motors, are accounted for in the net power measurement."Gaining two whole points of conversion efficiency in this type of system is phenomenal," says Bruce Osborn, SES president and CEO. "This is a significant advancement that takes our dish engine systems well beyond the capacities of any other solar dish collectors and one step closer to commercializing an affordable system."Serial #3 was erected in May 2005 as part of a prototype six-dish model power plant at the Solar Thermal Test Facility that produces up to 150 kilowatts (kW) of grid-ready electrical power during the day. Each dish unit consists of 82 mirrors formed in a dish shape to focus the light to an intense beam.The solar dish generates electricity by focusing the sun's rays onto a receiver, which transmits the heat energy to a Stirling engine. The engine is a sealed system filled with hydrogen. As the gas heats and cools, its pressure rises and falls. The change in pressure drives the pistons inside the engine, producing mechanical power, which in turn drives a generator and makes electricity.More here:http://www.sandia.gov/news/resources/releases/2008/solargrid.html

Topic by ewilhelm    |  last reply


do resistors use up power? Answered

i.e. is a circuit with resistors much less efficient than having the correct voltage/current from the course? i'm thinking here mainly about dimmer switches and also parallel LEDs where each would need its own resistor. Cheers.?

Question by jamesjamesjames    |  last reply


What is the difference between an in line 6 car engine and a v6 car engine in terms of performance? Answered

I currently own a 1989 Mercedes 260 e series and it has a in line 6 engine under the hood. I was wondering what the difference between an in line 6 and a v6 are in terms of performance like efficiency and horsepower.

Question by bobert610    |  last reply


Jevons Paradox

I recently read a thought-provoking article in the New Yorker: "The Efficiency Dilemma" by David Owen. The main gist of the article is that as our machines use less energy, we use them more, thus negating any environmental benefit we hope to achieve. This is known as "Jevons Paradox". You can read the abstract and article here, but you have to be a subscriber for the full article. You can read a commentary, with excerpts, here. Please discuss...

Topic by aeray    |  last reply


Optimisation of pneumatics

Another interesting thing I found through research, a flaw in most over-under designs and pressurizing the stock, I have found that for every 90 degree elbow between the chamber and the barrel the resistance to the air is the same as adding 20 feet of straight pipe, this can be changes by using two 45 degree fittings put together to make a gentler turn or by using curved fittings instead of elbows, the gentler the turn the better. From this I have found that the simple straight cannon with the chamber directly behind the barrel as is shown in the picture below (please note this cannon is one I found from Google just to emphasize the point, and this is in pneumatics only). also to increase efficiency look at my other topic:https://www.instructables.com/community/best_chamber_to_barrel_ratio/(once again if you have found my research incorrect please tell me, I wont get fired up =)

Topic by cheeseboy    |  last reply


Why is not all the energy transfered from the firing pin to the bullet in a K'nex gun? Answered

When the firing pin hits the bullet in a K'nex gun, why is there some energy lost? If all the energy from the firing pin was to transfer to the bullet, then the pin would stop before it hit the back of the gun. Is there some way to use all of the firing pin's energy to completely transfer to the bullet?

Question by ~KnexBuild~    |  last reply


Voltage Stabilizer Efficiency Loss (Extra power consumption)

Hello All, I am using an 1KVA Voltage stabilizer for my Fridge. The power quality is really poor here in India, and these things are mandatory. I learnt the lesson hard way :-(.... Well that aside, i would like to know what would be the power loss or Extra consumption these devices use when regulating power. Actually,i could use a general lecture on how Stabilizers work!

Topic by Zen Innovations    |  last reply




what are some math problems to make a efficient circuit? Answered

I am trying to make my own wind mill using a stepper motor, capacitor,led, and a resister. My problem is that my dad wants me to make it more efficient meaning making the led go brighter and longer. I curently have 11 capacitors in parallel ,one resister. what are some math equations i can use to find out how to make this more efficient and how do i use the problems? 

Question by lookwhatjoeysmaking    |  last reply


Simple, efficient, low-cost, solar energy equipment

I am looking for a DIY simple, low-cost solar water heater and solar light that will work in any kind of weather and still be able to supply atleast some working heat and light. Please suggest.

Topic by rseni    |  last reply


What would be the Easiest and most efficient way to make this?

I need a circuit that has a switch between 3 and 5 minute off times and a 3-5 second on time that repeats.  It needs ot ahve an on off switch and be as as efficient and compact as possibly, and fairly easy to make. Thanks in advance for any help! I need to order parts for it, so the parts I need would be nice.

Question by aarroozz    |  last reply


Hydrogen for renewable energy storage- total system efficiency?

This is a question that has been bugging me for some time, especially since the questions about methanol synthesis revived my interest in energy storage. Say I have a wind turbine or solar panel or whatever, that produces 1000 Wh per day.  If I use that electricity to electrolyse water, store the generated hydrogen at roughly atmospheric pressure in an upside-down water butt or a big gas-tight bag in my shed (don't worry, I'm not going to actually do this) and then feed it into a generator converted to run on H2, what percentage of that initial energy input would I get back out?  20%?  5%? 1%? The follow-up questions to this are a) How does that compare against a battery bank? What about a similar DIY-style pumped water storage system? b) What one component of the system should be improved to raise the overall system efficiency? Electrolyser, storage, generator? c) Are there any other DIY-friendly methods for storing intermittently generated electricity that I'm not thinking of? And, I suppose, d) Does doing this and providing 5-10x your overall power requirements in wind turbines work out cheaper than spending thousands on batteries?

Topic by PKM    |  last reply


Solar Power Towers Efficiently Using Brayton Cycle

I want to point out a solar to electric generation concept that has yet to be seen anywhere, even though it originated back during the Carter Administration's ERDA programs of the late 70's. I’m talking about solar power towers that convert solar energy into electricity at the hundreds of mega-watt level. While power towers do exist today, and the world currently does have a handful of them as shown in Fig-1, none use the Brayton Cycle nor can they boast an energy conversion efficiency at the mid to upper thirty percent level.  A group of engineers got together at a think tank organization called Sanders Associates in Nashua, N.H., several decades ago, and designed a unique Brayton Cycle, 100 MW solar Power Tower concept for generating electricity. This was accomplished under ERDA (Energy Research Development Administration) who gave us a phase-2 follow-up contract that took our phase-1 design and built a working scale model at the 10 KW level. This model was tested at the Georgia Tech Solar Research Facility and "registered" ~37% electric solar conversion efficiency. The system used ambient air as its working fluid, and was to be located in open-spaced desert regions. Phase-2 was lost to competition using a closed-loop liquid sodium system that boiled water into superheated steam at 900F to run a turbine that generated ~21% overall electric conversion efficiency.  Apparently, at that time ERDA would rather haul water out to the desert than use ambient air to generate electricity? The politics of their decision is beyond reason and clashes with improving the world’s development of green technology energy.  ERDA shut out our better technological performer and safely locked it away for another day! ERDA's official reason for turning us down: "this technology uses excessively high temperatures (2500F versus 900F) that are dangerous to workman maintaining the equipment". But that was back in the 70’s, maybe we’ve learned to deal with high-temp heat by now?   Solar Energy Concept Using Low Pressure Storage Our solar power tower would collect the sun’s energy by locating its ceramic heat exchanger on top of a tall tower as shown in Fig-1. The tower was located in the center of a field of active sun-searching mirrors (heliostats, Figure-2). These mirrors reflected sunlight onto our ceramic honeycomb heat exchanger, producing a concentrated flux intensity level that heated it to around 2500F. At the same time, low pressure fans generating only a few psi pressure would suck the ambient air through the honeycomb, heating it to just under the 2500F and then passing it through energy storage silos which stored the heat down to ~150F. We purposely designed the energy storage charging phase of our hot air system to work at only a few psi above ambient as a safety feature. The sun effectively acts as the combustor of our jet engine or Brayton cycle engine. Once the sun heats the air, it passes through heat exchangers consisting of a labyrinth of underground silos that are temperature segregated. These silos receive our 2300F airflow and cool it down to about 150F, transferring this heat into solid salt containers which turn to liquid once they have absorbed sufficient heat. Figure-3 is a schematic of this underground energy storage facility and shows the airflow being heated by a fully charged set of silos containing liquid salt-bricks. This airflow direction is reversed when we charge the silo’s salt-bricks. The bricks are kept in specially insulated, high pressure silos (located underground for added insulation) that store the heat energy at one atmosphere for later use. These underground silos act as our energy storage batteries, and when needed would discharge their heat energy accordingly into the moving airflow. This energy storage concept permitted the generation of electricity at night and during overcast days. Two sets of storage systems are required for continuous operation. One would be charging at low pressure while the other is discharging at high pressure through the Brayton engine to generate electricity.   Electric Energy Generation at High Pressure Electricity would be created by turning an electric generator at high speed. The generator was turned by running a jet engine connected to it.  The engine’s combustor for heating the air is effectively the sun, hence the name Brayton cycle for generating our solar electricity (Figure-4). The heat from the molten salt containers would increase the energy of the high pressure air coming from the compressor, and would then force it through a typical turbine that turns this energy into high rotational speed to run the generator and make electricity. Our solar jet engine sucks in ambient air using its compressor, as all jet engines do, and blows it through a series of silos at high pressure whose stacked bricks are held at different temperature levels. We start our airflow through a silo held as low as 150F and work our way up to ~2300F as we pass through our last, hottest silo which acts to complete the effective solar combustion process. This air preheating technique dramatically improves our energy turnover capability and allowed us to convert solar energy into electricity at near 37% efficiency. During our electric energy generation phase, the silos of our Brayton system requires operating at many atmospheres of pressure just as in any jet engine combustor using petroleum-based JP-fuel.      

Topic by RT-101    |  last reply


Higher efficiency (high amp) 12V regulator alternative to 7812

I need a high efficiency 12V DC regulator to supply my thermoelectric modules (they're very inexpensive so I had no choice but to use them). I found that the modules are most efficient at 12V @ ~7A each. I could use many 7812s in parallel but they are too inefficient and too much energy is lost to heat. Is there any alternative? Electricity bills are going up so it'd be very good if I can find an extremely efficient step-down or step-up regulator, short of using an expensive 'gold standard' ATX PSU (which are usually upwards of 500W so the power savings don't matter).

Topic by arikyeo    |  last reply


Boost curcuit amperage issue? Answered

I am planning to make a small boost converter similar to mintyboost. I am using a boost IC that will give me about 92% efficiency with the voltage i have. The output is 5v at 500ma, and the input voltage is 2.4v. Would the ic suck up more than 500ma per hour from the batterys?

Question by astroboy907    |  last reply


The Newman Motor Challenge !

I was recently approached by someone claiming the old Newman Motor wouldn't be good for anything.Well, I was a little bit offended by this as I already had my little toy version of it as kid.At that time though it really was just a toy for me.Critics still say the Newman Motor is nothing more than some interesting machine.And even the biggest followers will admit it is not a free energy machine, just a very efficient one.I experimented with, what some call fringe science, now for about 30 years.And it all started with math and my interest in unusual ways of dealing with problems.So what's behind the challenge?The original design was suprisingly simple as you can see in the above Wiki link.Just a spinning magnet in a (split) coil.What you don't find anywhere though is real details on the how to.Sure, you need to have some sort of contact linked to the rotation and timing is critical but what does it all do?You can build a drt simple model in a few hours with stuff you might have around already.Quite a few Youtubers are happy to share their creations.The actual challenge is to come up with what Newman really did inside his drum.And also why I think it is not the full potential his machine had.Build a simple Newman motor and check for how long you can let it run on a charge super capacitor.Then sit back and read some of the other magnet stuff I wrote.After that come up with a better design ;)I started to create some 3D models that need testing once I find more free time - should take some leave one day..But for those with little patience and an interest in the Newman Motor I decided to share my current idea:For some it might be really confusing although they know motors and magnetic fields.Those just playing with magnets might have it easier for once as they can pretend they followed my thoughts ;)The original design used two coils and a rotating magnet.If you consider how the magnet creates an electromagntic field in the coils then you have to wonder right away how it can spin.And most designs will indeed need a push start to get going!You can't have electricity produced without the magnet spinning and you can't make it spin without electricity!The current from the battery or capacitor can only flow at the short moment of contact on the axle.This moment needs to be timed "mechanical" as we don't want to waste any power on not required electronics.If you ever bothered to check the timing of a Newman Motor then you realised the collapsing electromagnetic field at the moment of contact actually is in reverse to what the manget has in that position.Unlike any normal motor it means the magnet produces most of the power the coil needs to make the rotor spin!So far for the well known facts, now for my fiction:I would like to call my version the Aussie Newman Motor as all things downunder are just different ;)Here are my current desing mods, that I freely share so everyone can benefit form many years of experimenting to save a lot of time.1. Instead of two coils a not-really-bifilar coil is centered on the axle.The coil is created like two stacked relay coild that have no bobbin and a "dint" to allow the axle to pass through.Without the big gap of the original less of the magnetic field strenght is lost and the coil is far closer to a homogenous magnet.2. The timing done by salvaging a simple DC motor's contacts and brushes.This allows for far higher currents and if the salvaged motor had enough poles also for a very short "burst".3. The axle contact is made with a cleaned steel bearing.After cleaning very conductive copper based lubricant is used in tiny amounts to prevent corrosion and provide a lower resistance.The clear benefit is that with the new timing system a lot more current can flow.Initial tests with a mock up model showed an increase in run time from the capacitor of about 15% already.With proper bearings and a salvaged DC motor I hope to reach 18 to 20% more than the original design.Now why the DC motor if a reed contact or hall effect sensor would be even faster and with less resistence?Neither can handle really high currents without additional electronics ;)Plus of course I wanted to leave the door open for the Aussie Newman Motor 2020.You might now say "Why bother if the above improvements are already so great?".If you followed my elsewhere for a while then you know the Newman Motor is only 2D but I prefer 3D or more harmony if you like.Right now the imagination of people re-inventing Newman's machine is limited.They try to get on the horse from behind - literally.Fancy electronics, machined parts and so on.But they never go 3D ;)You got it? :)There is only two coils!!The magnet rotates, same as the contact on the axle.One set of coils for each contact the salvaged DC motor has.Each set aligend to the corresponding contact.And now you will ask "How do you plan to connect that to a single DC power source?Well, that is why it will be the 2020 model - my time for tinkering is sadly limited because I still need to work to support myself.But if you consider that the original as a good model can run for over 10 minutes on a supercapcitor then ask yourself how long it could run on 4 or even 8 coil sets.And although there is no such thing as "free energy": There will be still space for more coils.Or other coils to just provide electricity that does not power the motor.Critics will now see their chance and state that if we add a load to these additional coils then this will cause a strain on the system.Of course they are correct here.If, however, the load is mechanical then the motor needs to supply basically the same additional energy.Plus all mechanical losses.The question is: How much mechanical load can we add before the motor is down to the same efficiency of a very efficient DC motor? ;)And what if our Aussie Newman 2020 would actually violate the laws of physics?We can calculate how much electrical energy would be required so a given motor produces a fixed amount of torque.Or we can just measure it, the beauty of science...We can do the same in reverse of course.Let's say a mechanical pump would require 500RPM and 100Nm of torque to pump 100 liters per minute.Then we could calculate what sized motor we need to drive the thing and how much power the motor would need.So again: What if the Aussie Newman 2020 would require far less than what science makes us think and still does this job on a simple 12V lead acid batty of 4Ah?Just saying... ;)I hope to have a presentable and working 2 coil system by May, so stay tuned!In case you are faster or even beter then of course feel free to show off your results or to post a link to your Instructable so everyone can verify it.

Topic by Downunder35m    |  last reply