{"id":2250,"date":"2011-05-18T21:42:04","date_gmt":"2011-05-19T04:42:04","guid":{"rendered":"http:\/\/www.corbinstreehouse.com\/blog\/2011\/05\/electric-bug-driving-and-watt-hours-per-mile\/"},"modified":"2011-05-18T21:42:04","modified_gmt":"2011-05-19T04:42:04","slug":"electric-bug-driving-and-watt-hours-per-mile","status":"publish","type":"post","link":"https:\/\/www.corbinstreehouse.com\/blog\/2011\/05\/electric-bug-driving-and-watt-hours-per-mile\/","title":{"rendered":"Electric Bug: Driving and watt-hours per mile"},"content":{"rendered":"<p id=\"top\" \/>\n<p>I now have over 3000 miles on my car. Up till today, the only problems I have had have been with the IOTA DC-DC Converter. I&#8217;m supposed to have a replacement soon, as my IOTA may fail again at any moment.<\/p>\n<p>Now that I have some driving experience, I have a better idea of the range. It&#8217;s not good to say that an electric car gets X mile range, since X various by many factors. Those factors are: how heavy you are with the pedal to accelerate, how hard and often you brake, how many hills you drive up and how fast you drive. I have one big hill on my commute (or, when I go *anywhere*), so I can never remove that factor, and I always want to drive at least the speed limit. But I can control how &#8220;soft&#8221; I drive.<\/p>\n<p>If I drive the car &#8220;soft&#8221;, meaning reasonable acceleration and driving at the speed limits on the freeway (usually 65 mph), I could get a 100 mile range to 0% State of Charge (SOC). Last Sunday I drove 64 miles according to my odometer (or, about 62 miles according to google maps). The BMS said it took 122.3 Amp-hours and the SOC was at 39%. This drive was mostly at 65mph, aside from the 2 miles driving up my &#8220;driveway&#8221;, and then going 50-55 up and down highway 17. I had maybe one stop light each way on my trip. 122.3Ah * 48 (number of cells) * 3.2V (nominal voltage per cell) = 18785 Watt-hours (18.8kW). 18785.28Wh \/ 64 miles = <b>294<\/b> <b>Watt-hours<\/b> per mile. The batteries are rated at 200Ah. So: 200Ah*48*3.2 = <b>30720 Watt-hours<\/b> of energy in the battery. 30720Wh \/ 294Wh\/mile = <b>104.5 miles.<\/b><\/p>\n<p>So, a good &#8220;soft driving&#8221; estimate for my bug, including a large hill and mostly 65 MPH on the freeway, is <b>104 miles.<\/b> Generally, I don&#8217;t want to do this, as taking the battery lower than 20% is not good for cycle life. I also don&#8217;t have my BMS setup to limit power when voltage drops to a certain level, so it is dangerous (meaning, I could cause damage to expensive cells).<\/p>\n<p>If you are doing a bug conversion, use about 300 Wh\/mile as an estimate for what you can get. I rarely get better Wh\/mile, but that is because of my huge hill I drive up. Wh\/mile would be better if I didn&#8217;t live in the Santa Cruz mountains.<\/p>\n<p>Now, if I drive &#8220;harder&#8221; I can get about 375 Wh\/mile. That&#8217;s about an 82 mile range. So, I can probably safely say my range is from <b>70 to 100 miles<\/b> per charge, but I probably won&#8217;t want to go more than 80 miles to keep it &#8220;on the safe side&#8221;.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I now have over 3000 miles on my car. Up till today, the only problems I have had have been with the IOTA DC-DC Converter. I&#8217;m supposed to have a replacement soon, as my IOTA&#8230; <a class=\"read-more\" href=\"https:\/\/www.corbinstreehouse.com\/blog\/2011\/05\/electric-bug-driving-and-watt-hours-per-mile\/\">[read more]<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[34],"tags":[],"class_list":["post-2250","post","type-post","status-publish","format-standard","hentry","category-electric-bug"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/posts\/2250","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/comments?post=2250"}],"version-history":[{"count":0,"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/posts\/2250\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/media?parent=2250"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/categories?post=2250"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.corbinstreehouse.com\/blog\/wp-json\/wp\/v2\/tags?post=2250"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}