Electric / hybrid aircraft propulsion (NOT cars)

Peter wrote:

And progress is very very slow. Like in medicine, really

Most of R&D is actually in production processes. Everything from producing and recycling lithium to the design of factories and the batteries themselves. The largest obstacle is not weight, but price, quality and to a lesser degree size (volumetric size). Progress is lightening fast in fact, much faster than even the most optimistic forecasts predicted. Physically Li batteries are good enough today to replace all transportation (except aviation).

This is from 2014

This is the actual from the end of last year:

Today it is already below US$200 per kWh. Tesla claims somewhere between US$ 150-200 per kWh

For aviation, this doesn’t look all that good, because weight matters a lot. For large scale conversion to electric propulsion, new battery technology is needed, and it certainly not obvious that this new battery technology is able to take advantage of the price development of Li batteries. But, the price of Li batteries, suitable motors and power electronics will soon be so low that people accept lower endurance for lots of “mission profiles”. Remember that the maintenance cost and hassle will literally be gone, the reliability will increase 10x or more, better than a TP. In a training setting, this means 100% availability. The fuel cost is only a fraction.

In any case, for certified GA, the biggest obstacle is certified GA itself. Airbus had some interest for a while, but it looks to have vanished by now. It was all just a publicity stunt I guess, a fun way to kill some time and EU research funding. Go down in the history books as the “first” to fly across the Channel, and that’s it. Siemens do have a nice package for aerobatics and similar short endurance stuff, which could create lots of extremely cool stuff, time will tell.

What I would like is:

• A sleek, aerodynamic single seater, fully aerobatic, maybe a tandem.
• 100 kW electric engine
• 10-50 kWh battery capacity, put in and out as needed
• Evinrude E-tec 30-50 kW range extender, super compact, light, maintenance free FADEC two stroke with the efficiency of a four stroke.
• A winch so I can tow gliders

It could cruise at 110 knots forever (limited by cheap mogas and the battery capacity), 200 knots for up to an hour. The technology is here, it’s commercially available. This thing could be built for less than € 50 k. This, or similar things are possible today. The problem is it requires so much experimenting and non-certifiable solutions that it will never see the light of day as a certified aircraft. As experimental and microlight, it’s more a problem of having the guts, stamina and time to do it. Someone will, I’m sure, but I don’t think it will be anything but a curiosity for some time yet.

Physically Li batteries are good enough today to replace all transportation

That is not true, no matter how one plays with the numbers.

I also think you might want to add “a hydro electric power station like they have lots of in Norway” to your list

Solar panels (mentioned in an earlier post) are also no good unless you drive or fly at night, or have a swappable battery pack (and about a square kilometre garden and live in Greece) and charge that while driving or flying

The other day I read these facts: An area of 43.000 square miles of solar panels would be necessary to power the whole planet. The Sahara desert has 3.6 milion square miles.

Draw a square of 335 × 335 km onto the Sahara in Google Earth and check how small that area is.

https://www.forbes.com/sites/quora/2016/09/22/we-could-power-the-entire-world-by-harnessing-solar-energy-from-1-of-the-sahara/#69a75a63d440

The other day I read these facts: An area of 43.000 square miles of solar panels would be necessary to power the whole planet. The Sahara desert has 3.6 milion square miles.

Wasn’t there a consortium of some pretty big German companies, called DeserTec or something, who wanted to install a huge scale solar power plant in the Sahara?

No idea. I guess the logistics/material etc are not easy to solve.
But I agree 100% with Achimha …. it is up to us to start these developments and the investment into the future.

Yesterday I read an interview iwth a German Car expert who was so arrogant to call Elon Musk a “three hit wonder” etc … Looks like many people in the car industry still don’t get it. While Tesla is showing them the future they still build 4 door sedans with V-8 engines and 600 hp. I know I am a hypocrite here, because I enjoy a smilar car, but I will switch to a Tesla whenever it will have enough range for my work, probably in less than 5 years. And I have to solve the charging topic where we live (downtown).

And to everybody who has not tried it: Test an electric car and THEN talk. I think they are a lot of fun too.

Here, found the DeserTec initiative:
http://www.desertec.org/

The main problems I see here are the unstable political situation in the Sahara countries and the technical problems of how to transmit the power generated to the end users in Europe.

It is also not free after installation.

The PV panels don’t just last for ever, with ~1kW/m2 hitting them and correspondingly high ambient temp. Especially not the cheap ones which is all one could use in such a large project. For the ones sold into the domestic market, a reasonable estimate is 25 years before you have to replace it all. The control electronics will most likely fail long before then; it’s not specially expensive but it means periodic maintenance is required overall.

I used to do a lot of business in this area, many years ago (electronics).

MedEwok wrote:

Wasn’t there a consortium of some pretty big German companies, called DeserTec or something, who wanted to install a huge scale solar power plant in the Sahara?

On last year at university on 1991/92, we visited Voith in Germany. Already at that time they presented (to us) their idea of building solar plants in Sahara to supply all of Europe with electricity. At that time, my thoughts were more like, “well, what would the beduins think about some Germans converting their land into a solar park” A typical “white man” solution to a problem the beduins do not have. Anyway, the idea has merit indeed, and it’s being done as we speak, although on a much smaller scale. The problem is still a political one though. Do we really want to be dependent on muslims in Africa for all our electricity? I guess not.

achimha wrote:

I assume you get your milk from your own cow which you sized exactly to fit your requirements?

LOL

Peter wrote:

That is not true, no matter how one plays with the numbers.

It is true, and you will find out by yourself IF you bother to play the numbers. – or you can “strengthen” your stand by reading all the 50 points I linked to earlier.

Peter wrote:

I also think you might want to add “a hydro electric power station like they have lots of in Norway” to your list

I work in hydropower. Frankly, the development of electricity production has started worrying me. The way it is going with solar power and battery storage, not even hydropower is able to compete on a price basis. The single most important aspect of hydropower is to be able to jump production from zero to max in a matter of seconds, without loosing any efficiency worth mentioning and without wasting energy. This is completely impossible for all other methods of producing electrical power (nuclear, thermal, bio, wind, solar). Therefore, electricity from hydropower is of much higher value than everything else. Energy can be stored, and used on demand within only seconds notice. However, the combination of solar power/wind and Li batteries seems to be more and more lethal. Just 5 years ago, the price of this combination made it laughable as a viable alternative. Within this decade, it seems solar + battery will become the cheapest method, certainly within the next decade, there is no doubt whatsoever. Sometime within the next decade, it is more likely that hydropower plants starts to be decommissioned rather than renewed or maintained. At the same time, also wind farms will become obsolete, they cannot compete with solar when the battery price drops sufficiently.

The whole thing is really very straight forward. Wind and solar charges batteries whenever the wind blows and the sun shines. Energy is tapped for consumption from the batteries. We will certainly see some big solar plants popping up here and there, but we will also see distributed production and storage in each individual home. A battery can ramp up from zero to max in a matter of milliseconds, it’s instant, only constrained by whatever “thing” that needs gradual ramping. The battery capacity in EVs themselves could be used as storage. If you are going away for a couple of days or more. Plug in your car and sell the storage capacity. It will be a very different reality of what we are used to today. The key component is Li batteries (combined with smart grids, solar power and an economy around it).