ToughButterCup Posted January 24 Share Posted January 24 At this time of year I always look for signs of encouragement - and one way is to look for the edges of Spring. Snowdrops, bird song, backbirds scrapping, buds beginning to swell a little. Walked put my myenergi thingy and saw the charge light lit up and 0.01 kWh ' in the bag ' First time this year I think. Spring is round the corner Link to comment Share on other sites More sharing options...
JohnMo Posted January 24 Share Posted January 24 Did 9kWh the other day from my vertical panels. Well pleased. Was just generating 3.2kW between the clouds, but wife has dishwasher and washing machine on, so that's all disappearing very quickly. 1 Link to comment Share on other sites More sharing options...
MikeSharp01 Posted January 24 Share Posted January 24 Cripes yes - let's hope so. Link to comment Share on other sites More sharing options...
SteamyTea Posted January 24 Share Posted January 24 Just had a quick look at my energy monitor, yesterday I used 5 kWh, a week ago, it was 22 kWh. Down to the small storage heater, and in Moron Gardens, flowers are coming out, and the fields are being cropped for daffodils. 1 Link to comment Share on other sites More sharing options...
ToughButterCup Posted January 24 Author Share Posted January 24 36 minutes ago, JohnMo said: Did 9kWh the other day from my vertical panels. Well pleased. Phhhhhh, jealous or what .... Vertical ? Never ever seen or heard of that. Photo ? Link to comment Share on other sites More sharing options...
SteamyTea Posted January 24 Share Posted January 24 7 minutes ago, ToughButterCup said: Vertical Catches the low winter sun better. Link to comment Share on other sites More sharing options...
JohnMo Posted January 24 Share Posted January 24 7 minutes ago, ToughButterCup said: Phhhhhh, jealous or what .... Vertical ? Never ever seen or heard of that. Photo ? Last 7 days generation, generation to grid actually goes into hot water. On cold frosty morning 1 Link to comment Share on other sites More sharing options...
JohnMo Posted January 24 Share Posted January 24 Have a 45 degree array on house also, but it is generally generating 1/3 or less the vertical generation, at this time of year. Link to comment Share on other sites More sharing options...
ToughButterCup Posted January 24 Author Share Posted January 24 I'm impressed. What about ( for example) wind-loading on those John? I'll dig around in your posts about solar PV now ...... Link to comment Share on other sites More sharing options...
JohnMo Posted January 24 Share Posted January 24 I used 4" posts with a 45 deg support on each post. All post-creted in place. Then unistrut horizontal to mount the panels to. Had 70 mph winds the other day and few other storms - no issues so far. 2 Link to comment Share on other sites More sharing options...
SteamyTea Posted January 24 Share Posted January 24 I like this sign of spring, though it is probably only temporary. Link to comment Share on other sites More sharing options...
ToughButterCup Posted January 24 Author Share Posted January 24 Jesus @SteamyTea, T shirt and flip flops yet? Link to comment Share on other sites More sharing options...
SteamyTea Posted January 24 Share Posted January 24 Just now, ToughButterCup said: Jesus @SteamyTea, T shirt and flip flops yet? They never come off, it is Cornish National Dress after all. 1 Link to comment Share on other sites More sharing options...
ToughButterCup Posted January 24 Author Share Posted January 24 1 hour ago, JohnMo said: I used 4" posts with a 45 deg support on each post. All post-creted in place. Then unistrut horizontal to mount the panels to.... It's the simplicity I like best. I'm building a south facing stone wall at the moment 4 feet high by 25 meters long. Debbie is planting herbs that do well in full sun on the bank next to the wall. I wonder how many panels I can get in there just like you've done ? And shunt the power generated there to a largish battery in her potting shed nearby : that should secure Senior Management Team buy in. Then we can get all those damn plants off the south facing kitchen window sill. 'Nother sleepless planning night ahead then Ian...... Thansk very much for the post @JohnMo Link to comment Share on other sites More sharing options...
SteamyTea Posted January 24 Share Posted January 24 1 minute ago, ToughButterCup said: shunt the power generated there to a largish battery in her potting shed nearby Could add a few degrees to the winter temperature as well. Link to comment Share on other sites More sharing options...
JohnMo Posted January 26 Share Posted January 26 Good sun day today. Battery fully recharged by lunchtime, left heat pump running and 2kW going into hot water via immersion at one point. Grid power is excess going back to the grid on the battery software, but really it goes direct to hot water via a diverter. It's plotted every 5 mins so peaks are missed. Wife just put the washing machine on, to use more electric. Link to comment Share on other sites More sharing options...
ToughButterCup Posted January 30 Author Share Posted January 30 (edited) Thats the trick isn't it John .... self consumption. I have a measly 3.8kWp and a 14kW SunAmp. That sucks up every last drop of solar that I can produce and then I export whatever is left. I'm eyeing up our new wall for potential to use vertical panels : standing there earlier today in bright sun @SteamyTea's point about vertical panels picking up sun at this time of year is driven home. In a Northerly wind, the pieces of stone are already a tiny bit warm to the touch. I have a feeling that there will be competition for that vertical space - I married a gardner. Maybe I can arrange to provide enough power to light our garden pathways. Edited January 30 by ToughButterCup Link to comment Share on other sites More sharing options...
SteamyTea Posted January 30 Share Posted January 30 (edited) 1 hour ago, ToughButterCup said: standing there earlier today in bright sun @SteamyTea's point about vertical panels picking up sun at this time of year is driven home. In a Northerly wind, the pieces of stone are already a tiny bit warm to the touch. Trigonometry, Power and Specific Heat Capacity. To keep things simple, assume the same light beam, with a power of 200 W.m-2, and using the sketch above. When the sun is at 90° to a surface, the area will be 100 mm by 100 mm, so 10,000 mm2, or in proper language 0.01 m2. The power per square meter is therefore 200 [W.m-2] x 0.01 [m2] = 2 W Angle the beam over by 30°, the area changes to 115.47 mm by 115.47 mm, so 0.0133 m2, 33% greater area, at 60° it is 200 mm by 200 mm, 0.04 m2, 4 times greater area. So it goes from 2 W of power, though 1.5 W at 30° to 0.5 W at 60°. If your wall was granite (or most stone/brick/cement) it has a specific heat capacity of around 0.8 kJ.kg-1.K-1. Now a W is a J.s-1, a small amount really. The density is around 2500 kg.m-3. Taking an area of 1 m2, but just the first 10mm of wall depth that is facing the sun, this will have a mass of 2500 [kg] / (1 [m] x 0.01 [m]) = 25 kg. So to heat up 25 kg of wall, by 1 K will take: 0.8 [kJ.kg-1.K-1] x 25 [kg] = 20 kJ of energy. At a power input of 200 W.m-2 (200 J.s-1), and not taking any losses into account (which will be quite a large fraction) to increase the temperature by 1 K will take: 20,000 [J] / 200 [J.s-1] = 100 s. At 30° light beam angle, 133 s, and at 60°, 400 s. Edited January 30 by SteamyTea 1 Link to comment Share on other sites More sharing options...
SteamyTea Posted January 31 Share Posted January 31 @ToughButterCup I made a bit of an error, should have said that both the sun altitude And azimuth angles are the same. If only one angle changes, then you get greater power. Link to comment Share on other sites More sharing options...
ToughButterCup Posted February 1 Author Share Posted February 1 You'll be proud of me, @SteamyTea. I've gone through your post above ( the one with all the numbers and and threatening signs [ like these] )at least half a dozen times and I think I'm fairly close to understanding it ..... sometime later this year. I'm a bit of a slow learner really. Link to comment Share on other sites More sharing options...
SteamyTea Posted February 1 Share Posted February 1 6 minutes ago, ToughButterCup said: I'm a bit of a slow learner really You can take the cosine of the incident angle and multiply that by an arbitrary length to get the new arbitrary length. Then divide the power by the length to see how much it reduces by. I may have to write it up proper sometimes instead of a quick reply. Or just go to PVGIS. 1 Link to comment Share on other sites More sharing options...
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