What do you think about "e-soaring"?

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John.Roo

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Electric Aircraft World Endurance Record
To promote Good idea, just one detail...
Organizers describe the support needed for the record flight:
“The flight team and support crew will include three pilots, five on-the-ground support crew, a second support (petrol-powered) plane, and two vehicles carrying recharging equipment for the aircraft."
As a fan of electric airplanes I am not sure if this is good way how to promote electric aviation. Why?
Zero emission electric plane will need petrol powered plane + two cars following him with chargers. To fly 1 150 km distance will require 18 stops to recharge / replace battery = in average means landing every 63 km. Will this really convince pilots of ICE powered airplanes that electric propulsion is a future?
And... is environmental friendly if one electric airplane is followed by two cars + ICE powered airplane?
What about to try to finally implement charger into electric airplane?
 

sming

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Apr 10, 2019
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You mean like the solar pulse? Which promoted the future of fly with zero emission but needed the crew of, what, 50-100 person + portable hangar to be flown at each legs xD
Without accounting with the constant flying around to pitch the project to big money...

I want my affordable electric motorglider now!
 

John.Roo

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Letohrad / Czech Republic
You mean like the solar pulse? Which promoted the future of fly with zero emission but needed the crew of, what, 50-100 person + portable hangar to be flown at each legs xD
Without accounting with the constant flying around to pitch the project to big money...

I want my affordable electric motorglider now!
You are 100% right - Solar Impulse had same problem. One pilot flying and 100 workers supporting.... Real challenge would be to have electric airplane independent on ground support. Like ICE airplane requesting just access to “fuel” / electric power.
Actually is “affordable” airframe, motor and controller. Problem is light 10-15 kW on board charger. And big problem is price of batteries for aviation. On board charger seems to be available soon. But batteries.... unless we will be able to buy batteries for similar price like automotive industry we cannot make “affordable” electric motorglider / airplane. Or we have to start with light oneseaters requesting only small power to stay in the air ;-)
 

dog

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Dec 29, 2019
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578
I met Eric Raymond personally on AERO Friedrichshafen long time ago.
View attachment 112009
(on photo you see tail of our OK-QUA98 and also electric EGO Trike of my friend) :cool:
Eric did amazing job - airframe of Sunseeker Duo is extremelly light. However 22 m wing span is far too much.
23 % solar panel efficiency allows to get only 5 kW of power from whole surface of wing and horizontal tail unit. Imagine - only 5 kW of power necessary to keep horizontal flight of two seater with MTOM 470 kg.
Better efficiency of solar panels could solve ongoing problem with energy density of batteries and move environmental friendly aviation to new level.
Somehow I had got the impression that 22m was not so great a span,and previously had no
interest in gliders until your and Victor Bravo's
love of gliding became infectious.
As to the efficiency of the glider to fly on 5kw,
that is something for everyone to think about.
There is a new type of tandem solar panel under intense development worldwide useing
perovskite cells layered over conventional silicone.These can convert sunlight at 40%
efficiency and add no real weight as it is a
molecular thin film.Problems that the technology had ,have been largely addressed
and testing is moving into the verification stage.The best silicone PV for sale is now just over 25% efficient.
One big worry of solar panel manufacturers is that the equipment that they install must now
be designed so that it can accomodate the next most likely advance,as having non adaptable equipment has already put major companys out of buisiness.
The upside of all of this is that the ROI has been so good in all aspects of solar power that
there are investors ready to put more money down on the next thing now.
Same on the battery side and its happening now in hydrogen tech.
That you and the people you know have been proving these technologys for aviation use is
a big thing and will make widespead adoption a
natural thing as the technology improves.
I do my own thing with solar living off grid and
get dragged into debates about all aspects of
this and beyond,which sometimes get difficult,
but when I state that it has been more than 10
years since I have paid a power bill,then this is
hard to find fault with.
Keep up the good fight.
 

John.Roo

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Joined
Oct 8, 2013
Messages
823
Location
Letohrad / Czech Republic
Somehow I had got the impression that 22m was not so great a span,and previously had no
interest in gliders until your and Victor Bravo's
love of gliding became infectious.
As to the efficiency of the glider to fly on 5kw,
that is something for everyone to think about.
There is a new type of tandem solar panel under intense development worldwide useing
perovskite cells layered over conventional silicone.These can convert sunlight at 40%
efficiency and add no real weight as it is a
molecular thin film.Problems that the technology had ,have been largely addressed
and testing is moving into the verification stage.The best silicone PV for sale is now just over 25% efficient.
One big worry of solar panel manufacturers is that the equipment that they install must now
be designed so that it can accomodate the next most likely advance,as having non adaptable equipment has already put major companys out of buisiness.
The upside of all of this is that the ROI has been so good in all aspects of solar power that
there are investors ready to put more money down on the next thing now.
Same on the battery side and its happening now in hydrogen tech.
That you and the people you know have been proving these technologys for aviation use is
a big thing and will make widespead adoption a
natural thing as the technology improves.
I do my own thing with solar living off grid and
get dragged into debates about all aspects of
this and beyond,which sometimes get difficult,
but when I state that it has been more than 10
years since I have paid a power bill,then this is
hard to find fault with.
Keep up the good fight.
Thxs for a very interesting info!
40% efficiency looks like a dream...
With this panels we could make interesting airplanes with more “normal” wing span (wing area).
I would love to test such a panels on small one seat light plane like Sunexelec.
Even if power from that panels on smaller wings will be lower that power necessary for horizontal flight we could use energy for “sponzored L/D”.
I have to “google” more info about new solar panel development ;-)
 

dog

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Joined
Dec 29, 2019
Messages
578
Thxs for a very interesting info!
40% efficiency looks like a dream...
With this panels we could make interesting airplanes with more “normal” wing span (wing area).
I would love to test such a panels on small one seat light plane like Sunexelec.
Even if power from that panels on smaller wings will be lower that power necessary for horizontal flight we could use energy for “sponzored L/D”.
I have to “google” more info about new solar panel development ;-)
No need to use guggle.
and this
and this last which is hit and miss but always
includes links
 

John.Roo

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Joined
Oct 8, 2013
Messages
823
Location
Letohrad / Czech Republic
No need to use guggle.
and this
and this last which is hit and miss but always
includes links
Evolution of solar panels looks interesting.
So far seems to me the best place for solar panels is the roof of hangar, but in few years who knows :) For use on airplane we need flexible solar panels and actually availabe flexible solar panels have an efficiency 20-21%.
Every % counts so I hope that efficiency 30% or more is realistic in near future.
 

Lukas Etz

New Member
Joined
Jun 10, 2019
Messages
2
yes - John.Roo is right - the developmernt of photovoltaic is great and 30-40% efficiency sounds great.
But in many cases it is not necessary to have the latest technology.
In my gliding club we installed a photovoltaic generator on the hangar roof with 47kWp.
While planing the solar system the limitating point was the gridconncetion (max grid feed-in is 30 kW), so there was no use to install a bigger generator. Even with very low price modules (low efficiency=18%) the hangar roof was not completly covered with modules.
On a good day in june the system is producing +300kWh and on a very bad winter day (without snow) about 10kWh. This is always more then the club is using on a daily base.
The combination of (roof installed) photovoltaik with electric gliders is so very perfect. Flying my MiniLakFES (sorry it´s not homebuilt) normally takes 2kWh for takeoff and jumping in the thermals. So in my club is always solar energy for many, many takeoffs.
Next good point is the price of the (low efficiency) solar technics. My clubfriends and me did the installation, so costs were low - about 500€/kWp. That means energy costs about 0,05 €/kWh if the system is working for 10 years or more. In Germany we get a feed-in-tariff of 0,08€/kWh - which is a pretty good deal.
 

John.Roo

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Messages
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Location
Letohrad / Czech Republic
yes - John.Roo is right - the developmernt of photovoltaic is great and 30-40% efficiency sounds great.
But in many cases it is not necessary to have the latest technology.
In my gliding club we installed a photovoltaic generator on the hangar roof with 47kWp.
While planing the solar system the limitating point was the gridconncetion (max grid feed-in is 30 kW), so there was no use to install a bigger generator. Even with very low price modules (low efficiency=18%) the hangar roof was not completly covered with modules.
On a good day in june the system is producing +300kWh and on a very bad winter day (without snow) about 10kWh. This is always more then the club is using on a daily base.
The combination of (roof installed) photovoltaik with electric gliders is so very perfect. Flying my MiniLakFES (sorry it´s not homebuilt) normally takes 2kWh for takeoff and jumping in the thermals. So in my club is always solar energy for many, many takeoffs.
Next good point is the price of the (low efficiency) solar technics. My clubfriends and me did the installation, so costs were low - about 500€/kWp. That means energy costs about 0,05 €/kWh if the system is working for 10 years or more. In Germany we get a feed-in-tariff of 0,08€/kWh - which is a pretty good deal.
That is the way I like 👍

MiniLak with FES is a beautiful small self launch glider.
Here you can see report
(Google will help you with translation) :cool:
In article (or on Internet) you can find many informatons, however most important for now is that battery in MiniLak has capacity of 4,2 kWh (32 kg) and charger has power of 1,2 kW. So it is easy to imagine how many solar panels (even standard versions with lower than 20% effifiency) you need for safe re-charging.
 

blane.c

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HBA Supporter
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capital district NY
The government is encouraging solar.

 

blane.c

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Location
capital district NY
Thanks for interesting post 👍
From my point of view maybe could be this concept interesting for "normal" airplanes.
I see main advantage in small dimensions.
However gliders and motorgliders - especially actual generation - are usually even more efficient.
What makes them more efficient?
 

John.Roo

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Letohrad / Czech Republic
What makes them more efficient?
Performance of latest versions of gliders is amazing.
L/D over 50 = really low power requested for horizontal flight.
Maybe I am wrong, but key seems to be high wing aspect ratio, reduction of "corners" etc. Generally is about looking where would be possible to reduce drag. I didn´t noticed application of new profiles - mostly are done only small modifications / optimalizatoins of existing ones.
At some point is priority safety and flight characteristics. And sometimes has also effect conservative mind of pilots (especially glider pilots) :) Therefore we don´t see that many gliders with "V" tail surfaces or "flying wings".

Another reason for more "classic" design are also certification requirements.
Unless you ae able to reach very low EW to stay in "deregulated" area you need to deal with authorities. And if pilots are sometimes "conservative" than authorities are "ultra-conservative" :)

So in short....
Biplanes, boxed wings, flying wings etc. are usually solving one problem (lower drag, higher lift etc.) but in opposite they add complications like non-standard flight characteristics, higher airframe weight, complicated and sometimes really expensive certification.
 
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John.Roo

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It is really sad to see increasing prices of batteries....
Price of 1 kWh of bateries for aviation from professional producers is actually far over 1 000 EUR. And price... price is the key to increase amount of electric airplanes between pilots and aeroclubs.
Why are electric bicycles best selling electric machines? They are affordable. Of course you still can buy very expensive bicycle, however they are also cheaper models affordable for everybody. If you pay lower price you are aware of shorter range (or lower power etc.) and parts produced in China, but it is acceptable because is still easy to use.
If parts of propulsion (motor, controller, battery cells, BMS, sensors.... ) are produced in China it doesnt automatically mean that system will be not safe. It is only necessary to test optimal combination of parts and probably cooperate also with some electric bicycle producers.
It also means that is necessary to stay in one-seater category.
Lower requested power = less problems with heat, cables, connectors etc.
Is time to make some tests :)
 

John.Roo

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Letohrad / Czech Republic
This concept has one problem.... like all human powered aiprlanes requests perfect health condition of pilot :)
Look again to electric bicycles - they can be used practically by everybody.
Doesn´t matter if you young bodybuilder or 80 year old lady.
Electric propulsion with low power, low ("affordable") price, simple to use... no human power requested :)
 

henryk

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krakow,poland
Electric propulsion with low power, low ("affordable") price, simple to use... no human power requested
=or hybrid=man power +electric servo...

=or better "amplifier" (resonant harnees + clean,light wing)=

"Oscillating Wing Propulsion"

=or=
 

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John.Roo

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=or hybrid=man power +electric servo...

=or better "amplifier" (resonant harnees + clean,light wing)=

"Oscillating Wing Propulsion"

=or=
I would stil prefer to don´t use human power ;)
Pilot should be perfectly focused on flying.
Also... how much power can you get from non-trained human?
Professional well trained athlete as able to "produce" 300 W constantly for one hour.
I can´t imagine that "normal" pilot will give you more than 100 W.
Most likely will be less....
Young pilot has a lot of energy, but no experience. Let him concentrate 100% on controls and traffic.
Old pilot has a lot of experience, but he is able to "produce" less energy + older pilots are typically very lazy :)
Combination of power (electric and human) is adding complexity to construction = more weight = more power requested for flying etc.
Lets try to keep it simple ;)
 
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