UK solar doldrums

[metrologist]

only 78Wh yesterday.

[ahbushnell]

only 78Wh yesterday.

What fraction of the year do you get "usable" power? 

[metrologist]

don't know, just tossed it out on the patio table a few months ago. I've not been keeping records either, just casual glances at the watt meter - 158Whr today. Solar insolation here is generally 4.5.

[fourtytwo42]

Well don't despair entirely in January I have done better the last few day's allowing the weekly rolling average to lift to a dizzying 0.6Units per day so far this week Long may it continue!

[metrologist]

I just have it connected to a tired old FLA. I'm not sure if my SCC does the right charge cycles so I may consider monitoring that somehow. I set the terminate voltage to 13.5 and it looks like the SCC just goes to a trickle charge at that voltage. It does let me select one of three difference LA battery types, so it must be doing something different for each one.

[splin]

The OP's sunshine shortage is not an isolated incident.

Sunshine is in short supply across a swathe of north-west Europe, shrouded in heavy cloud from a seemingly never-ending series of low pressure systems since late November and suffering one of its darkest winters since records began

It's not just the UK.

Belgium’s Royal Meteorological Institute has declared December 2017 “the second darkest month since 1887”, when it began measuring, after the 10.5 hours of sun recorded at its Uccle weather station last month were beaten only by a bare 9.3 hours in 1934.

From https://www.theguardian.com/world/2018

It does highlight the problem with large scale PV in these northern climes; lots of power in midsummer when demand is lowest and b*gger all in winter when it's needed most. And it doesn't help that inter-seasonal storage is hellishly expensive - perhaps the only viable option being synthesised liquid fuels, or possibly gas for which long term storage costs aren't totally out of reach. Unfortunately, I understand the cost and efficiency of the synthesis processes are very poor.

The interesting question (to me) is should PV play any worthwhile role in these low insolation regions if renewables are to reach close to 100% of total generation? In winter the only viable source is wind. But if you have enough turbines to cover winter, alongst with short term storage (and FF backup for the occasional one or two week doldrums that can cover much of Europe) then you likely have more than enough wind generation in summer as well - average wind speeds may be lower than winter but demand is also much lower.

So why bother with PV? It obviously would be useful supplying power when there is no wind but the economics would be terrible - the viability of PV in the UK at present is predicated on being able to sell all the annual generation at reasonable prices which would not be available for large parts of the year when the wind is blowing.

[Edit] Fixed typos.

[fourtytwo42]

It does highlight the problem with large scale PV in these northern climes; lots of power in midsummer when demand is lowest and b*gger all in winter when it's needed most. And it doesn't help that inter-seasonal storage is hellishly expensive - perhaps the only viable option being synthesised liquid fuels, or possibly gas for which long term storage costs aren't totally out of reach. Unfortunately, I understand the cost and efficiency of the synthesis processes are very poor.

My intention was to keep the post to personal or small scale systems as a whole new dimension of issues apply at a national level that I think have been discussed elsewhere.  As for wind or water power I am not gifted in location and in any case small scale wind is sadly outlawed by planning requirements for those with a normal sized garden.

[metrologist]

I also wanted to install a small wind generator. We get a stiff breeze many afternoons, but I'll have to check the regulations on it.

My panel is in a poor spot, blocked in the AM by clouds/fog and noon hours by building and tree. I get full sun on it starting about 1pm. I moved it and set it up more perpendicular to the sun and managed a 250Wh day.

There is this new global darkening I hear now?

[fourtytwo42]

I also wanted to install a small wind generator. We get a stiff breeze many afternoons, but I'll have to check the regulations on it.

My panel is in a poor spot, blocked in the AM by clouds/fog and noon hours by building and tree. I get full sun on it starting about 1pm. I moved it and set it up more perpendicular to the sun and managed a 250Wh day.

There is this new global darkening I hear now?

If your in the uk the rule is base must be at least as far from any boundary as the tower height plus blade length, that pretty well knackers you from getting up enough to avoid ground turbulance and building/tree shadow in most domestic gardens

Thats a pretty good result for solar, I got 1.1U yesterday and the monthly average finaly lifted from 0.3U/day to 0.4!!

I guess your talking about atmospheric pollution rather than the sun going out

[paulca]

Tehe.

I averaged about 120mW power yesterday with the odd spike to 300mW.

It's an indoor 50W system though.  Saturday was different.  I got quite a long period of 15-25W.

[grifftech]

I have solar, but it is a 6vdc system

[fourtytwo42]

Tehe.

I averaged about 120mW power yesterday with the odd spike to 300mW.

It's an indoor 50W system though.  Saturday was different.  I got quite a long period of 15-25W.

Perhaps you forgot to draw the curtains yesterday! Good today though
Some days with my 1Kw outdoor system you would think it's covered in curtains too, maybe 15W if lucky so 1.5%! Don't you count as a no GTI but keep records man in the survey ?

[fourtytwo42]

I have solar, but it is a 6vdc system

It all counts, mine pushes DC (sometimes a bit chopped) into the hot water tank heater and only converts to AC to use any surpless from that.

[paulca]

Perhaps you forgot to draw the curtains yesterday! Good today though
Some days with my 1Kw outdoor system you would think it's covered in curtains too, maybe 15W if lucky so 1.5%!

It's in my vampire cave, but it's on the daylight side of the curtains.

Haven't looked at today's graph, no point.  The sun did come out briefly at one point, but the battery voltage moved from 12.1 to 12.2. 

And my last downstream lithium just low voltage alarmed.

[paulca]

I know this is UK, but I'm up at 54.5* North.  It's only just got to being barely daylight when I leave for work at 8:20am and there was a tiny hint of light in the sky at 5:00 when I left for home.    I hate this time of year.

Of course in June it's the other way.

[paulca]

Hmmm.   The graph suggests it did okay.

[fourtytwo42]

Hey cool paul, is that a PI ?

I collect mine with a PIC in an EEPROM for dynamic display on an LCD and only periodically dump the data to produce a graph on the PC, my last looked like this to the beginning of December and I know from the LCD it got down to 0.3U/day late Dec / early Jan. Horizontal axis is hours, vertical is unit's per day and its rolling averaged over 7 days.
Going by the LCD display things are at last picking up again so guess I will do another dump and new graph beginning of Feb.

Of course cannot wait for summer, hoping to drive my big outdoor woodsaw from it this year

[paulca]

Hey cool paul, is that a PI ?

Kinda.  It's a PI and an ESP8266.  This more or less:

https://www.eevblog.com/forum/projects/nodemcu-esp8266-rs485-epever-solar-monitor-diy/
https://www.eevblog.com/forum/beginners/finally-got-my-first-project-actually-complete/

It's moved on a bit.  I now have the RRDs automated, 1 once per minute for all data.  Graphs are done by rrdgraph.

It's a bit "how you doing" at the moment.  It all works, but it's kinda like breadboard.  I have to log in and run commands to generate graphs.  I hope to make it generate them daily and create web pages for each group of data.

Graphs could be prettier too.  The RRA databases contain data for 10 years and can produce daily, weekly, monthly, yearly graphs or any time window or parameters you want.  Multiple data sources can be overlayed, stacked etc.  There are web UIs for it, I might resort to one for convenience.

[Blocco]

I also wanted to install a small wind generator. We get a stiff breeze many afternoons, but I'll have to check the regulations on it.

If your in the uk the rule is base must be at least as far from any boundary as the tower height plus blade length, that pretty well knackers you from getting up enough to avoid ground turbulance and building/tree shadow in most domestic gardens

I wonder whether the same regulations apply to mobile structures i.e. a mast mounted on a trailer or vehicle.

[paulca]

Today looks like a cracker over here in Northern Ireland.  It's been 5-10% cloud all day so far.

https://www.windy.com/?clouds,54.615,-5.713,10,m:fcfafZG

Does anyone know where you can get "sun" power levels on a weather forecast?

[fourtytwo42]

I also wanted to install a small wind generator. We get a stiff breeze many afternoons, but I'll have to check the regulations on it.

If your in the uk the rule is base must be at least as far from any boundary as the tower height plus blade length, that pretty well knackers you from getting up enough to avoid ground turbulance and building/tree shadow in most domestic gardens

I wonder whether the same regulations apply to mobile structures i.e. a mast mounted on a trailer or vehicle.

I assume you mean pseudo mobile as in stuck in your garden then yes and frankly the guy's would have to be at a greater radius than a road vehicle. If you mean a 20ft mast on a road going vehicle I think your chances of getting down your road before being pulled up by the police are nill.

[fourtytwo42]

Today looks like a cracker over here in Northern Ireland.  It's been 5-10% cloud all day so far.

https://www.windy.com/?clouds,54.615,-5.713,10,m:fcfafZG

Does anyone know where you can get "sun" power levels on a weather forecast?

Not seen it, I just go by the cloud cover given in https://www.netweather.tv/weather-forecasts/uk/today/2520~((%20Belfast%20))#forecast for example and your place doesnt look to good today while mine is cool

Thanks so much for the links to the software, makes my efforts using GnuPlot look primative!

[paulca]

Thanks so much for the links to the software, makes my efforts using GnuPlot look primative!

No problem.  The easier solution is to install a linux distro's version of "Cacti" and hack in a datasource for whatever you want.  Usually just a script based one.  Cacti takes care of the rest, although it can be a bit fiddly at first understanding the different names for things.

[fourtytwo42]

Things are slowly picking up here in the new year I just dumped this primative chart in units/day averaged over a week, bottom scale is hours.

[paulca]

Things are slowly picking up here in the new year I just dumped this primative chart in units/day averaged over a week, bottom scale is hours.

I'm going to try and produce some graphs to work out if my system is consuming more internally than it's actually producing on grey days   Yes it's that bad here.  Monday was a cracker though.  Tuesday and today, rubbish.  Days are getting longer though.