{"id":8364,"date":"2019-01-09T17:18:20","date_gmt":"2019-01-09T16:18:20","guid":{"rendered":"http:\/\/www.theoillamp.co.uk\/?p=8364"},"modified":"2019-01-09T17:20:42","modified_gmt":"2019-01-09T16:20:42","slug":"declining-renewables-output","status":"publish","type":"post","link":"https:\/\/www.theoillamp.co.uk\/?p=8364","title":{"rendered":"Declining renewables output"},"content":{"rendered":"

Something I have been thinking about for a while is declining renewables output.\u00a0 I said last year that I thought my solar PV output was declining in a previous blog.\u00a0 I read an article in the Guardians’ weatherwatch in which the author said his PV output was declining in passing although he did not allude to any reasons why.\u00a0 The other week the same weatherwatch feature also said the planet is becoming less windy.<\/p>\n

This latter fact is surprising.\u00a0 Climate change was expected to make it stormier.\u00a0 Of course the two are not mutually exclusive.\u00a0 Average wind speeds could drop with much more violent winds at times.<\/p>\n

The wind drop is global.\u00a0 The Guardian article put forward some theories.\u00a0 One was that vegetation cover was increasing as are built up areas.\u00a0 Both tend to slow wind down.\u00a0 If vegetation cover is increasing then this is good news I thought it was decreasing.\u00a0 In any case these are not the explanation.\u00a0 Wind speeds are decreasing in Saudi Arabia which has little of either.<\/p>\n

The wind speed decreases are taking place at ground level and its unknown as to whether they will affect wind turbine output.\u00a0 It does seem likely however.<\/p>\n

My solar PV drop does not seem as bad when plotted out (below) or analysed statistically*.\u00a0 The data is shown for my oldest system.\u00a0 The newer one shows the same trend but there is less data and not enough to do stats on (and the number of years is odd).\u00a0 The red line shows the linear trend and the equation at the bottom the trendline equation and the R2<\/sup> value a measure of how significant the linear regression is.\u00a0 The answer is not very and the paired test bears this out.\u00a0 The drop is not statistically significant.<\/p>\n

\"solar<\/a>This surprised me.<\/p>\n

The question is if wind and solar output are declining why is it and what can we do about it?\u00a0 There are several possible solutions to declining renewables output .\u00a0 We could add more wind and solar capacity to compensate.\u00a0 We could add better technology.\u00a0 This is happening anyway with solar cell efficiency hitting 50% rather than that of my cells which is around 20%.\u00a0 And we can add different technology.\u00a0 Tidal for the UK seems the obvious answer.\u00a0 (Wave tends to follow wind output).\u00a0 In other countries it could be completely different. Its pretty obvious we should be overly reliant on one form of renewables anyway.<\/p>\n

Happy new year Neil<\/p>\n

*For those interested you can divide a dataset in 2 and do a paired test.\u00a0 I need an even number to do it.\u00a0 My new system is an odd number of years.\u00a0 To remove one year could introduce bias, also for the new system there are too few years to do a normality test first. The data for the old system was divided in 2 and each half was tested for normality.\u00a0 One set was normal the other was not.\u00a0 This means you use a non-parametric (non normal) test.\u00a0 I used Wilcoxon matched pairs in PSPP.\u00a0 This is an open source version of SPSS which I have used in the past and found to give the same answers as SPSS.<\/p>\n","protected":false},"excerpt":{"rendered":"

Something I have been thinking about for a while is declining renewables output.\u00a0 I said last year that I thought my solar PV output was declining in a previous blog.\u00a0 I read an article in the Guardians’ weatherwatch in which … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[5,15,4,1],"tags":[],"class_list":["post-8364","post","type-post","status-publish","format-standard","hentry","category-climate-change","category-practical-low-carbon-living","category-renewables","category-uncategorized"],"yoast_head":"\nDeclining renewables output - The oil lamp - shining God's light on peak oil<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.theoillamp.co.uk\/?p=8364\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=8364\",\"url\":\"https:\/\/www.theoillamp.co.uk\/?p=8364\",\"name\":\"Declining renewables output - The oil lamp - shining God's light on peak oil\",\"isPartOf\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=8364#primaryimage\"},\"image\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=8364#primaryimage\"},\"thumbnailUrl\":\"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2019\/01\/solar-PV-output-300x169.jpg\",\"datePublished\":\"2019-01-09T16:18:20+00:00\",\"dateModified\":\"2019-01-09T16:20:42+00:00\",\"author\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f\"},\"breadcrumb\":{\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=8364#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.theoillamp.co.uk\/?p=8364\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=8364#primaryimage\",\"url\":\"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2019\/01\/solar-PV-output-300x169.jpg\",\"contentUrl\":\"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2019\/01\/solar-PV-output-300x169.jpg\"},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/?p=8364#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.theoillamp.co.uk\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Declining renewables output\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/#website\",\"url\":\"https:\/\/www.theoillamp.co.uk\/\",\"name\":\"The oil lamp - shining God's light on peak oil\",\"description\":\"Blogging by Neil and Andy about Peak oil and faith.\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.theoillamp.co.uk\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f\",\"name\":\"admin\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g\",\"caption\":\"admin\"},\"url\":\"https:\/\/www.theoillamp.co.uk\/?author=1\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Declining renewables output - The oil lamp - shining God's light on peak oil","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.theoillamp.co.uk\/?p=8364","twitter_misc":{"Written by":"admin","Est. reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.theoillamp.co.uk\/?p=8364","url":"https:\/\/www.theoillamp.co.uk\/?p=8364","name":"Declining renewables output - The oil lamp - shining God's light on peak oil","isPartOf":{"@id":"https:\/\/www.theoillamp.co.uk\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.theoillamp.co.uk\/?p=8364#primaryimage"},"image":{"@id":"https:\/\/www.theoillamp.co.uk\/?p=8364#primaryimage"},"thumbnailUrl":"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2019\/01\/solar-PV-output-300x169.jpg","datePublished":"2019-01-09T16:18:20+00:00","dateModified":"2019-01-09T16:20:42+00:00","author":{"@id":"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f"},"breadcrumb":{"@id":"https:\/\/www.theoillamp.co.uk\/?p=8364#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.theoillamp.co.uk\/?p=8364"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.theoillamp.co.uk\/?p=8364#primaryimage","url":"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2019\/01\/solar-PV-output-300x169.jpg","contentUrl":"http:\/\/www.theoillamp.co.uk\/wp-content\/uploads\/2019\/01\/solar-PV-output-300x169.jpg"},{"@type":"BreadcrumbList","@id":"https:\/\/www.theoillamp.co.uk\/?p=8364#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.theoillamp.co.uk\/"},{"@type":"ListItem","position":2,"name":"Declining renewables output"}]},{"@type":"WebSite","@id":"https:\/\/www.theoillamp.co.uk\/#website","url":"https:\/\/www.theoillamp.co.uk\/","name":"The oil lamp - shining God's light on peak oil","description":"Blogging by Neil and Andy about Peak oil and faith.","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.theoillamp.co.uk\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/b6f2831189b0d01294e9672bb540ba6f","name":"admin","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.theoillamp.co.uk\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/2070f70411f2eab27f08cd0b2332e27e3987c781423ecba6c16b575181ce2a6a?s=96&d=mm&r=g","caption":"admin"},"url":"https:\/\/www.theoillamp.co.uk\/?author=1"}]}},"_links":{"self":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/8364","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=8364"}],"version-history":[{"count":2,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/8364\/revisions"}],"predecessor-version":[{"id":8367,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=\/wp\/v2\/posts\/8364\/revisions\/8367"}],"wp:attachment":[{"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=8364"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=8364"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.theoillamp.co.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=8364"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}