I know that this is how it is generally done. In this topic I am asking for alternatives. Looking for alternatives makes sense because of probable lower cost, higher efficiency (less energy conversions), and durability (less components to break).
Here are some articles on this:
I hope that direct heaters are already available to buy. If not do you know of anything that is easier to make and cheaper than this? I like this.
kPower surveyed heating by kinetic energy and found no attractive similarity cases where heat is made directly and cheaply. The explanation in part is that Nature favors using energy in multiple stages from order to entropy, that a direct jump from kinetic to thermal squanders.
I gave some in this thread. A better search should give more. I also gave some of the reasons for looking into it.
By āattractiveā, I meant major engineering cases where kinetic energy is converted directly to heat in a proven cost-effective application. One example is rubbing hands in cold, as an occasional resort, but where is another existing case?
Kites are proven in roles of transporting masses. Future megascale applications range from dredging up dikes to combat sea-level rise to transporting water for agriculture and pumped hydro.
Note that my power kite mentor, Dave Culp of KiteShip, was a key expert in the Cal Tech megalith lifting demo cited above.
The reason why the convertion mechanical -> thermal is uncommon is, because the most common primary energy source is fuel. Just burn the stuff to generate heat! Itās harder to generate mechanical work from these sources.
Doubt it. Will be easier to do conventionally just like the megalith could have just been lifted by a crane any time and wasnāt transported to the demo site by a kite.
I have operated and directed cranes up to 600ton rating, and we took up this topic at KiteShip. Cranes require road or water access and do not reach high altitudes.
A huge kite can be hauled in pieces almost anywhere.
The kite dredging idea competes with fuel-based dredges. One has to have a green ethos or like kites to prefer it.
Daisy has used both a brake and a generator to control torque.
Both systems generated heat ā¦
The heat on the brake disk was wasted to the environment. = bad
The generator filled a battery which drove heating elements in kettles often making good tea as a useful by productā¦ = yummy
If you can quantify a good kinetic to heat energy conversion method and use case, then go for it.
Otherwise electric is darn handy
This crane chat is very hypotheticalā¦
Helicopterā¦
Applying Kites at any cost is not an ecologic answer. If a wilderness exists where a crane canāt access then planning laws likely aught to determine that area off limits to development for conservation reasonsā¦ where needs dredged? Harbours (boat dredgers) canals (cranes on the tow path) ploughing (tractors)
I would say water pumping and water treatment trough filter. Both case are in fact just water pumping. Water treatment is of main concern in a vast proportion of places. You donāt treat water, you pollute your soil with untreated excrement plus you loose that water. Treat that water and you keep it, plus you donāt pollute.
Making and using a ground-based water brake AWES. The winch converts rotational energy into heat without the involvement of electricity, so off-grid, by using a water brake as a Joule machine replacing the ground-based generator. The storage is also assured with (hot) water. An AWES could heat one or several houses.
If a yo-yo AWES is used the intermittent use (reel-in and reel-out phases) is less problematic than with a generator, thanks to permanent heat storage. Only a motor or a spring is used to wind the tether.
Other ground-based AWES comprising rotary devices could also be used, such like Daisy or SuperTurbine ā¢.
Below is a link for complete explains by using a wind turbine of type Savonius. An easy adaptation could be made for AWES:
Some extracts:
Heat versus Electricity
On a global scale, thermal energy demand corresponds to one third of the primary energy supply, while electricity demand is only one-fifth. In temperate or cold climates, the share of thermal energy is even higher. For example in the UK, heat counts for almost half of total energy use. If we only look at households, thermal energy for space and water heating in temperate and cold climates can be 60-80% of total domestic energy demand.
Direct heat production is cheaper, more energy efficient, and more sustainable than indirect heat production.
The Water Brake Windmill
Heat generating windmills convert rotational energy directly into heat by generating friction in water, using a so-called āwater brakeā or āJoule Machineā. A heat generator based on this principle is basically a wind-powered mixer or impeller installed into an insulated tank filled with water. Due to friction among molecules of the water, mechanical energy is converted into heat energy. The heated water can be pumped into a building for heating or washing, and the same concept could be applied to industrial processes in a factory that require relatively low temperatures.
Also by the link I provided before, one can see the figure 3 which shows some details which are perhaps common with the device described in the previous message, such like the belt transmission. So an AWES like @Kitewinder kiwee could also be a candidate.
Figure 3 | Development of a Wind Directly Forced Heat Pump and Its Efficiency Analysis :
6. Conclusions
The experiment results suggested that driving the heat pump system directly with the wind force can reduce the energy conversion losses during the processes of wind force energy converting to electric energy and electric energy converting to kinetic energy [ā¦].
So, unlike the device presented previously, this system seems to include a generator and looks more complex, and also more features such as air conditioning.
I also think that this is to be studied seriously, thinking especially about the device linked previously (water brake) without generator. We may eventually understand that intermittent renewables are not well suited to the electrical grid beyond hydro pumped-storage plant capacities, and that a significant portion of energy needs can be met off-grid. At the less AWES could avoid the issue of the grid in addition to the cost of generators and batteries.
An advantage is to have some possibilities for having the conversion system at the ground. Some adaptation should be studied due to wind direction changes.
That said AWES would have to avoid housesā¦Also a (not AWES) VAWT could perhaps be more suitable, or even an AWES version of VAWT, so a carouselā¦
But above all I am thinking of a reeling mode (yo-yo) with an automated flexible kite (less material, more power, and also more studied), with some adjustments between the winch and the water brake.
My take is that while you may end ip with slightly more heat than the heat you could get with an electric AWE turbine combines with a heat pump in the house, the value of heating is far less than electricity, because heat has little utility and is hard to store.
This, together with the observation that a heat AWE rig and the electrical one are of similar complexity, leaves me thinking this is a dead end.
Finally, on a business side, I think most customers would be more comfortable buying a wind power plant and a heating systems as two separate units, rather than combining these into one. This will probably also get the total price down due to economy of scale.
Even more finally; the water/paddle load is very limited compared to using an electric generator as a load. The power from AWE may require matching the load at subsecond time accuracy. This is trivial in the electric domain, but a real challenge with the water/paddle design.
So really I have trouble finding anything worthwhile going this direction. Sorry
Indeed, this point is problematic.
However, an alternative solution would be to feed a generator for heating.
Whatever the type of conversion system, and this also should apply to other intermittent energies, an off-grid arrangement is preferable.
For the foreseeable future, I donāt see any AWES connected to the grid or towing freighters.
On principle Iāll disagree with most of your points. Insulation and piping will cost roughly the same to you however much you buy of it, so no real economy of scale going on there. I can size and number the kites that Iām selling you based on your heating needs, and advise you on the size of storage tank that should go with that and maybe build it for you. I think costs increase pretty linearly for exponential increases in capacity, like the LO-FA windmill from the article. While for electrical generation they start high and only increase from there. Thatās the most important point that I think dwarfs most of the others.
Heat can be stored from summer to winter, like you can see in all those solar buildings with thermal storage. Thatās perhaps a better solution for residential heating.
This likely depends on your system. For rotary systems, like for regular wind turbines, it may not.
The biggest drawback I can see is the transport of the water.
The economy of scale comes in because there are millions air-to-air heat exchange heaters installed worldwide, but there will only be a few of these kite rigs in comparison (10.000 units would be a huge success?). And we didnāt even get started with matching the capacity of the heater to the house heating needs. From my point of view we are looking at hand crafting each installationā¦
An eddy current water heater is more efficient than a joule heater at rotation speeds of up to 600 rpm as shown in the attached report.
http://www.bulipi-eee.tuiasi.ro/archive/2013/fasc.4/p12_f4_2013.pdf
Here are some details.
