{"id":10472,"date":"2015-10-19T13:04:59","date_gmt":"2015-10-19T20:04:59","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=10472"},"modified":"2015-10-19T13:04:59","modified_gmt":"2015-10-19T20:04:59","slug":"g4-to-hy4-swapping-batteries-for-fuel-cells","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/g4-to-hy4-swapping-batteries-for-fuel-cells\/","title":{"rendered":"G4 to HY4 &#8211; Swapping Batteries for Fuel Cells"},"content":{"rendered":"<p>The University of Stuttgart and Pipistrel started down similar paths around 2007, with the Stuttgarters attempting a hydrogen-powered two-seat aircraft, the <a href=\"http:\/\/cafefoundation.org\/v2\/pdf_eas\/2009\/SteffenGeinitz_2009.pdf\">Hydrogenius<\/a>; and Pipistrel developing a self-launching craft with either two-stroke power or an equivalent electric motor.<\/p>\n<p><iframe loading=\"lazy\" title=\"Pipistrel Taurus G4 Electric Aircraft winner of $1.35M NASA Google &quot;Green Flight Challenge 2011&quot; -1\" width=\"500\" height=\"375\" src=\"https:\/\/www.youtube.com\/embed\/O0JhS_HuMvg?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/p>\n<p>The two groups came to rely on one another, with hydrogenius using the forward fuselage and wings of the Taurus G2 with hydrogen tanks in the fuselage and a Sineton motor on the tail.\u00a0\u00a0 On <a href=\"http:\/\/www.ifb.uni-stuttgart.de\/egenius\/page_Making-Of\/\">February 27, 2008, <\/a>Professor Rudolf Voit-Nitschmann, the father of the\u00a0solar powered aircraft Icare 2 and the unofficial World Record holder for distance flown in a solar powered aircraft, along with dipl. ing. Steffen Geinitz and dipl. ing. Len Schumann met with Pipistrel leaders, including CEO Ivo Boscarol and designer Tine Tomazic at the company headquarters in Ajdovscina.<\/p>\n<div id=\"attachment_10476\" style=\"width: 538px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-hydrogenius-systemintegration.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-10476\" class=\"size-large wp-image-10476\" src=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-hydrogenius-systemintegration-528x294.jpg\" alt=\"Hydrogenius as originally conceived\" width=\"528\" height=\"294\" srcset=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-hydrogenius-systemintegration-528x294.jpg 528w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-hydrogenius-systemintegration-300x167.jpg 300w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-hydrogenius-systemintegration.jpg 640w\" sizes=\"auto, (max-width: 528px) 100vw, 528px\" \/><\/a><p id=\"caption-attachment-10476\" class=\"wp-caption-text\">Hydrogenius as originally conceived. \u00a01. Hydrogen tank. \u00a02. Radiator. \u00a03. Stack module (hydrogen fuel cell). \u00a04. System module (hydrogen fuel cell). \u00a05. Power distribution unit. \u00a06. LiPoly battery to start the fuel cell system. \u00a07. Total rescue system<\/p><\/div>\n<p>Because the area aft of the wing was different for the Pipistrel G2 and Hyrogenius, the fuselages looked entirely different.\u00a0 Hydrogenius used the volume behind the wing to stow the H2 tank and mounted the Sineton motor high on the vertical stabilizer.\u00a0\u00a0 Pipistrel used that same area to house its retractable powerplant, whether electrically- or gasoline-powered.<\/p>\n<div id=\"attachment_10477\" style=\"width: 538px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/Pipistrel-electro-G2-air-to-air.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-10477\" class=\"size-large wp-image-10477\" src=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/Pipistrel-electro-G2-air-to-air-528x397.jpg\" alt=\"Pipistrel Taurus Electro in flight.  Now just imagine using two of these with a large center section holding two fuselages together and you have a G4, or a HY4\" width=\"528\" height=\"397\" srcset=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/Pipistrel-electro-G2-air-to-air-528x397.jpg 528w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/Pipistrel-electro-G2-air-to-air-300x225.jpg 300w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/Pipistrel-electro-G2-air-to-air.jpg 640w\" sizes=\"auto, (max-width: 528px) 100vw, 528px\" \/><\/a><p id=\"caption-attachment-10477\" class=\"wp-caption-text\">Pipistrel Taurus Electro in flight. Now just imagine using two of these with a large center section holding two fuselages together and you have a G4, or a HY4<\/p><\/div>\n<p>When NASA and the CAFE Foundation announced plans for the Green Flight Challenge, over a dozen entrants stepped forward.\u00a0 By the time the competition finally took place in September, 2011, only four teams had managed to complete an aircraft, and only two of those were electrically-powered \u2013 Pipistrel\u2019s G4, a twin-fuselage adaptation of the G2, and e-Genius, modified to battery power from its original hydrogen configuration.\u00a0 The Phoenix motorglider flew with a Rotax engine and the Embry Riddle mild hybrid used a Rotax\/electric motor\/generator combination.<\/p>\n<p>Results showed how well the two teams exceeded the requirements of the Challenge.\u00a0 The G4 and e-Genius were essentially the most efficient aircraft in the world.<\/p>\n<p>Pipistrel&#8217;s G4 took first place with an average speed of 113.6 mph, fuel economy (converted to electrical equivalents) of 403.5 passenger miles per gallon. \u00a0e-Genius was close behind, cruising at 107.3 mph and achieving 375.7 pmpg (e).<\/p>\n<div id=\"attachment_10484\" style=\"width: 310px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-pipistrel-G4.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-10484\" class=\"size-full wp-image-10484\" src=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-pipistrel-G4.jpg\" alt=\"This may be the German Air Taxi of the near future\" width=\"300\" height=\"650\" srcset=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-pipistrel-G4.jpg 300w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-pipistrel-G4-138x300.jpg 138w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><p id=\"caption-attachment-10484\" class=\"wp-caption-text\">This may be the German Air Taxi of the near future<\/p><\/div>\n<p>Taja Boscarol, Public Relations Manager for Pipistrel wrote, \u201cThe twin-fuselage Taurus G4 won NASA&#8217;s $1.35 million prize in [2011\u2019s] Green Flight Challenge as the world&#8217;s first 4-seat electric aircraft. The G4 flew 250 miles with the average speed higher than 100 miles per hour and the fuel consumption of less than one gallon per passenger.<\/p>\n<p>As noted in our reports during the event, the aircraft could have flown at least another half hour.\u00a0 \u201cOne thing remained, the final weigh-in of pilots and gear and fuel remaining in the petrol-powered aircraft. For the electric craft, a battery rundown test showed that e-Genius and the G4 had a half-hour&#8217;s reserve capacity, as required by the rules. Each was run at half-throttle for an hour to determine whether this requirement was met. Each met that goal and the G4 was run well beyond the hour as a final indication that the airplane could have gone considerably farther than the Challenge course.\u201d<\/p>\n<div id=\"attachment_10478\" style=\"width: 538px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/DLR-Hy4.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-10478\" class=\"size-large wp-image-10478\" src=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/DLR-Hy4-528x297.jpg\" alt=\"DLR's HY4 uses the G4 airframe, a hydrogen hybrid power system\" width=\"528\" height=\"297\" srcset=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/DLR-Hy4-528x297.jpg 528w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/DLR-Hy4-300x169.jpg 300w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/DLR-Hy4.jpg 800w\" sizes=\"auto, (max-width: 528px) 100vw, 528px\" \/><\/a><p id=\"caption-attachment-10478\" class=\"wp-caption-text\">DLR&#8217;s HY4 uses the G4 airframe, a hydrogen hybrid power system<\/p><\/div>\n<p>Even with this demonstrated range potential, the G4 does not begin to match that of the German Aerospace Center\u2019s (Deutsches Zentrum f\u00fcr Luft- und Raumfahrt; DLR\u2019s) HY4 project, essentially the G4 re-powered by hydrogen fuel cells to reach 466 to 932 miles.\u00a0 Power will be delivered to an 80-kilowatt motor, compared to the <a href=\"http:\/\/en.sv-jme.eu\/data\/upload\/2011\/12\/02_2011_212_Tomazic_04.pdf\">150 kW motor on the G4<\/a>.\u00a0 This raises some questions on performance we might expect for the HY4, especially for takeoff runs and rate of climb.\u00a0 The gross weight is approximately the same for the GFC winner and the DLR project.<\/p>\n<p>To overcome some difficulties, HY4 uses a hybrid system, with the main power coming from low-temperature Proton Exchange Membrane (PEM) fuel cells, which DLR claims, will \u201ccontinuously [supply] the electric motor with durable and reliable power.\u00a0 A high-performance lithium battery covers peak power loads during take-off and when climbing [to] altitude.\u201d<\/p>\n<p>With a maximum speed of 200 kilometers per hour (124 mph) and a cruise of 145 kilometers per hour (90 mph), HY4 will cruise about 23 mph slower than its GFC version.\u00a0 This will enable longer range without any other changes, but the ostensibly improved power system should be more efficient and the hydrogen fuel storage should allow longer endurance, and hence increased range.<\/p>\n<p><a href=\"http:\/\/www.dlr.de\/dlr\/en\/desktopdefault.aspx\/tabid-10081\/151_read-15429\/#\/gallery\/20921\">According to the DLR<\/a>, the HY4 will be the world&#8217;s first four-passenger aircraft powered solely by a hydrogen fuel cell battery system. \u00a0Joseph Kallo, their Coordinator of Electrical Aviation says, &#8220;With the HY4, we want to bring electromobility to the air, demonstrating the feasibility of this technology and identifying specific fields of application in passenger transport.&#8221;<\/p>\n<p><a href=\"http:\/\/www.dlr.de\/tt\/en\/desktopdefault.aspx\">DLR\u2019s Institute of Engineering Thermodynamics<\/a>, working on the design of the power system, hopes to achieve first flights with the HY4 at Stuttgart Airport in the summer of 2016.<\/p>\n<div id=\"attachment_10481\" style=\"width: 538px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr_HY4-stuttgart-airport.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-10481\" class=\"size-large wp-image-10481\" src=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr_HY4-stuttgart-airport-528x297.jpg\" alt=\"DLR HY4 flying over Stuttgart Airport, soon to be the test site for the airplane\" width=\"528\" height=\"297\" srcset=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr_HY4-stuttgart-airport-528x297.jpg 528w, http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr_HY4-stuttgart-airport-300x169.jpg 300w\" sizes=\"auto, (max-width: 528px) 100vw, 528px\" \/><\/a><p id=\"caption-attachment-10481\" class=\"wp-caption-text\">DLR HY4 flying over Stuttgart Airport, soon to be the test site for the airplane<\/p><\/div>\n<p>Kallo sees HY4 as part of an Air Taxi network \u201cto connect destinations more flexibly and offer faster alternatives to existing routes and means of transport.&#8221; \u00a0\u00a0As promoted by Dr. Brien Seeley and his Sky Taxi concept, electric aircraft are well suited to short to intermediate distances and their ability to take off and land on short because of their high torque.\u00a0 Adding wheel motors for enhanced acceleration would augment such capabilities.<\/p>\n<p>DLR points out that, \u201cWith more than 60 regional and international airports, Germany has a well-developed, extensively distributed network and already possesses the appropriate infrastructure for the implementation of this approach.\u201d Andr\u00e9 Thess, Director of the\u00a0DLR Institute of Engineering Thermodynamics\u00a0adds, &#8220;The HY4 four-seat electric aircraft perfectly matches our strategy to develop synergies between electromobility on the road and in the air.&#8221;<\/p>\n<p>DLR is joined by fuel cell maker <a href=\"http:\/\/www.hydrogenics.com\/about-the-company\/news-updates\/2015\/10\/15\/hydrogenics-joins-german-h2fly-consortium-to-enable-zero-emission-passenger-flights-using-fuel-cell-technology\">Hydrogenics<\/a>; <a href=\"http:\/\/www.pipistrel.si\/\">Pipistrel<\/a>, maker of the original G4; the <a href=\"https:\/\/www.uni-ulm.de\/en\/university.html\">University of Ulm<\/a> as a scientific partner, and <a href=\"http:\/\/www.stuttgart-airport.com\/?langredir=false\">Stuttgart Airport<\/a> as home airport for the project.\u00a0 DLR spin-off\u00a0<a href=\"http:\/\/h2fly.de\/\">H2FLY<\/a>\u00a0will operate the HY4 and will be responsible for the certification process.<\/p>\n<p>It\u2019s interesting and exciting to see Green Flight Challenge competitors partnering to take the most efficient aircraft in the world to new levels of performance.<\/p>\n<div id=\"facebook_like\"><iframe src=\"http:\/\/www.facebook.com\/plugins\/like.php?href=http%3A%2F%2Fcafe.foundation%2Fblog%2Fg4-to-hy4-swapping-batteries-for-fuel-cells%2F&amp;layout=standard&amp;show_faces=true&amp;width=500&amp;action=like&amp;font=segoe+ui&amp;colorscheme=light&amp;height=80\" scrolling=\"no\" frameborder=\"0\" style=\"border:none; overflow:hidden; width:500px; height:80px;\" allowTransparency=\"true\"><\/iframe><\/div>","protected":false},"excerpt":{"rendered":"<p>The University of Stuttgart and Pipistrel started down similar paths around 2007, with the Stuttgarters attempting a hydrogen-powered two-seat aircraft, the Hydrogenius; and Pipistrel developing a self-launching craft with either two-stroke power or an equivalent electric motor. The two groups came to rely on one another, with hydrogenius using the forward fuselage and wings of [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[15,3,14],"tags":[6799,6796,6804,6803,800,6797,6798,1274,6800,6805,1275,1706,1106,1220,6795,6801,918,1907,880,6802],"class_list":["post-10472","post","type-post","status-publish","format-standard","category-electric_powerplants","category-gfc","category-sustainable_ga","tag-andre-thess","tag-deutsches-zentrum-fur-luft-und-raumfahrt","tag-dipl-ing-len-schumann","tag-dipl-ing-steffen-geinitz","tag-dlr","tag-dlr-hy4","tag-dlrs-institute-of-engineering-thermodynamics","tag-e-genius","tag-h2fly","tag-hydrogenics","tag-hydrogenius","tag-ivo-boscarol","tag-joseph-kallo","tag-pipistrel-g4","tag-professor-rudolf-voit-nitschmann","tag-stuttgart-airport","tag-stuttgart-university","tag-taja-boscarol","tag-tine-tomazic","tag-university-of-ulm"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>G4 to HY4 - Swapping Batteries for Fuel Cells - CAFE Foundation Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"http:\/\/cafe.foundation\/blog\/g4-to-hy4-swapping-batteries-for-fuel-cells\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"G4 to HY4 - Swapping Batteries for Fuel Cells - CAFE Foundation Blog\" \/>\n<meta property=\"og:description\" content=\"The University of Stuttgart and Pipistrel started down similar paths around 2007, with the Stuttgarters attempting a hydrogen-powered two-seat aircraft, the Hydrogenius; and Pipistrel developing a self-launching craft with either two-stroke power or an equivalent electric motor. The two groups came to rely on one another, with hydrogenius using the forward fuselage and wings of [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"http:\/\/cafe.foundation\/blog\/g4-to-hy4-swapping-batteries-for-fuel-cells\/\" \/>\n<meta property=\"og:site_name\" content=\"CAFE Foundation Blog\" \/>\n<meta property=\"article:published_time\" content=\"2015-10-19T20:04:59+00:00\" \/>\n<meta property=\"og:image\" content=\"http:\/\/cafe.foundation\/blog\/wp-content\/uploads\/2015\/10\/dlr-hydrogenius-systemintegration-528x294.jpg\" \/>\n<meta name=\"author\" content=\"Dean Sigler\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Dean Sigler\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"6 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"http:\\\/\\\/cafe.foundation\\\/blog\\\/g4-to-hy4-swapping-batteries-for-fuel-cells\\\/#article\",\"isPartOf\":{\"@id\":\"http:\\\/\\\/cafe.foundation\\\/blog\\\/g4-to-hy4-swapping-batteries-for-fuel-cells\\\/\"},\"author\":{\"name\":\"Dean Sigler\",\"@id\":\"http:\\\/\\\/cafe.foundation\\\/blog\\\/#\\\/schema\\\/person\\\/e9c06a89f78d39fc03473ec90f4902a7\"},\"headline\":\"G4 to HY4 &#8211; Swapping Batteries for Fuel Cells\",\"datePublished\":\"2015-10-19T20:04:59+00:00\",\"mainEntityOfPage\":{\"@id\":\"http:\\\/\\\/cafe.foundation\\\/blog\\\/g4-to-hy4-swapping-batteries-for-fuel-cells\\\/\"},\"wordCount\":1128,\"commentCount\":0,\"image\":{\"@id\":\"http:\\\/\\\/cafe.foundation\\\/blog\\\/g4-to-hy4-swapping-batteries-for-fuel-cells\\\/#primaryimage\"},\"thumbnailUrl\":\"http:\\\/\\\/cafe.foundation\\\/blog\\\/wp-content\\\/uploads\\\/2015\\\/10\\\/dlr-hydrogenius-systemintegration-528x294.jpg\",\"keywords\":[\"Andr\u00e9 Thess\",\"Deutsches Zentrum f\u00fcr Luft- und Raumfahrt\",\"dipl. ing. 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