{"id":902,"date":"2012-12-02T22:59:01","date_gmt":"2012-12-02T21:59:01","guid":{"rendered":"http:\/\/www.sciencetronics.com\/greenphotons\/?p=902"},"modified":"2025-06-16T18:38:18","modified_gmt":"2025-06-16T16:38:18","slug":"magic-lights-in-uppsala","status":"publish","type":"post","link":"https:\/\/www.sciencetronics.com\/greenphotons\/?p=902","title":{"rendered":"Magic lights in Uppsala"},"content":{"rendered":"

Today the art festival “all lights on Uppsala” ended and Christmas season officially started with the 23rd annual fireworks by the local newspaper UNT.<\/p>\n

\"23rd<\/a>
23rd UNT fireworks in Uppsala<\/figcaption><\/figure>\n
\"All<\/a>
All lights on Uppsala – Gillbergska genomfarten<\/a><\/figcaption><\/figure>\n

During the festival, the artists and the city officials wanted to emphasize why LEDs will be the light source of the future. At one of the installations the efficiency of the humble incandescent light bulb was compared to the LED. There everyone passing by could read that the incandescent light bulb “converts 75% of the energy into heat and only 25% into light”.
<\/p>\n

\"The<\/a>
The Uppsala incandescent light bulb – 25% efficient!<\/figcaption><\/figure>\n

I tried to reach the responsible people already in the first week of the festival, but only got a reply after 2 1\/2 weeks. At that time it was considered too late to correct it to the correct number: an incandescent light bulb is much better than pointed out. Not only 75% of the electric energy is converted into heat, but rather 97.5%. Only about 2.5% of the electric power is converted into light! <\/p>\n

But in the believe of their 25% efficient incandescent light bulbs it is probably understandable that the city of Uppsala even this year continues to use incandescent lights in their Christmas illumination – while Stockholm has abandoned the use of incandescents for this purpose two years ago.<\/p>\n

\"Incandescent<\/a>
Incandescent Christmas lights in Uppsala 2012.<\/figcaption><\/figure>\n

I myself continue to use LEDs in my Christmas decorations<\/a>. Last year the LED conversion bulbs for the 7-lighted window decorations were only sold in packs of 4 – kind of stupid, unless you had enough of these decorations or wanted to take apart some of the bulbs. This year at least Biltema<\/a> is selling packs of 7 in two different versions: one with two 3mm LEDs inside the bulb, and one with a single diffuse 5mm LED inside. Both of them appear to be even better than last year’s versions – both in light color and manufacturing quality.<\/p>\n

\"\"<\/a>
A 2011 vintage Christmas LED light bulb.<\/figcaption><\/figure>\n
\"\"<\/a>
Biltema 88-723 – a 2012 Christmas LED light bulb (6 lm version).<\/figcaption><\/figure>\n
\"\"<\/a>
Biltema 88-721 – a 2012 Christmas LED light bulb with two 3mm LEDs inside (12 lm version).<\/figcaption><\/figure>\n

\"LED-bulbs<\/a>
LED-bulbs from Biltema<\/figcaption><\/figure><\/p>\n","protected":false},"excerpt":{"rendered":"

Today the art festival “all lights on Uppsala” ended and Christmas season officially started with the 23rd annual fireworks by the local newspaper UNT. During the festival, the artists and the city officials wanted to emphasize why LEDs will be the light source of the future. At one of the installations the efficiency of the […]<\/p>\n","protected":false},"author":1,"featured_media":904,"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":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"enabled":false},"version":2}},"categories":[8,40,19,28],"tags":[],"class_list":["post-902","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-everything_en","category-leds","category-photography_en","category-politics_en","entry","has-media"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/www.sciencetronics.com\/greenphotons\/wp-content\/uploads\/2012\/12\/IMGP0062a_800.jpg","jetpack_shortlink":"https:\/\/wp.me\/p48grL-ey","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/902","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=902"}],"version-history":[{"count":12,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/902\/revisions"}],"predecessor-version":[{"id":2481,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/posts\/902\/revisions\/2481"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=\/wp\/v2\/media\/904"}],"wp:attachment":[{"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=902"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=902"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sciencetronics.com\/greenphotons\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=902"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}