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Sunpower Diary A SOLAR ENERGY PROJECT DIARY |
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Day 120: Friday, Dec. 28, 2007. Took a reading in the morning before leaving for a few days. Total generated: 781. Day 114: Saturday, Dec. 22, 2007. The winter solstice. Sunrise 7:24 a.m., sunset 4:27 p.m. Nine hours of daylight and only about eight of them are sufficient to operate the system. Day 113: Friday, Dec. 21, 2007. This has not been a good week. Snow and cold -- collectors often covered, furnace and dryer running. Our average generation in the past week was only 1 KWH a day and our total daily use went up 1 KWH. Today: 1 KWH for a total of 763 since August 31 turn-on. National Grid meter 837. Day 107: Saturday, Dec. 15, 2007. Generated 3 for 757 KWH. National Grid meter 734. Day 100: Saturday, Dec. 8, 2007. 1:50 p.m. Generated 2 for 744 KWH. Startup was 7:55 a.m. System estimates that it has avoided generation of 967 pounds of carbon dioxide during its 970 hours, 9 minutes of operation. Day 99: Friday, Dec. 7, 2007. 12:30 p.m. Generated 2 for a total of 742 KWH. N.G. meter at 611. It has been a poor week -- very little direct sun. Skies often white overcast; cold, heat is running; and we have a Christmas tree in the yard that's on 24/7. Average daily use is up from 13.1 in November to 17.1 KWH. Average daily generation down from 8.0 in October and 5.7 in November to 2.7 this week. Hopefully it will clear up and we will get some sun! Day 97: Wednesday, Dec. 5 2007. We have had a little snow over the past few days and I noticed yesterday if not the day before that it has not blown off the solar collectors They remain partly covered with a thin layer of snow. Day 92: Friday, Nov. 30, 2007 12:55 p.m. National Grid meter 510. System on at 7:35 a.m. Generated 8 for a total of 722 KWH. An estimated 938 pounds of CO2 generation avoided. 912:33 hours of operation. Max output:2,918 watts. Day 85: Friday, Nov. 23, 2007 1:15 p.m. National Grid meter 458. System on at 7:45 a.m. Generated 4 for a total of 677 KWH. 880 pounds of CO2 generation avoided. 856:14 hours of operation. Max output 2,918 watts. Day 80: Sunday, Nov. 18, 2007 3:00 p.m. National Grid meter 412. Generated 9 KWH for 661 total. Day 78: Friday, Nov. 16, 2007 Generated 4 KWH today, total generated: 648. Overcast much of the week and rainy Thursday so we generated only 41 KWH but used 97. That would be 56 purchased from National Grid. Usually we generate more than we buy from them. Day 77: Thursday, Nov. 15, 2007 Rainy and gloomy, generated only 1 KWH for 644 total. Day 76: Wednesday, Nov. 14, 2007 3:20 p.m. Generated 9 for 643 KWH, National Grid meter 378. Day 75: Tuesday, Nov. 13, 2007 3:30 p.m. Generated 7 KWH for 634 total. Day 74: Monday, Nov. 12, 2007 3:15 p.m. Generated 2 for 627 total KWH. National Grid meter 365. Day 72: Saturday, Nov. 10, 2007 6 KWH, 613 total generated, National Grid meter 352. Day 71: Friday, Nov. 9, 2007 System turned on ten weeks ago today, August 31. We generated 6 KWH that day and 6 KWH today. Total generated, 607 KWH. Average daily generation has been 8.5. National Grid meter is 344 so our total electricity use in 71 days has been 951 KWH, an average of 13.4 KWH a day. Day 70: Thursday, Nov. 8, 2007 3:00 p.m. System on 7:15 a.m., generated 3, total generation 601, National Grid meter 335. Day 69: Wednesday, Nov. 7, 2007 Sunrise 6:39 sunset 4:43 4:15 p.m. System on 7:10 a.m. Generated 3 KWH for 598. National Grid meter 327. Day 67: Monday, Nov. 5, 2007 1:10 p.m. System on 7:00 a.m. Generated 8 for a total of 585 KWH. National Grid meter 320. Avoided generating an estimated 10 pounds of carbon dioxide today for a total of 760 pounds. Day 66: Sunday, Nov. 4, 2007 3:50 p.m. System on 7:05 a.m., generated 5 for total of 577 KWH. National Grid meter 313. Day 65: Saturday, Nov. 3, 2007 5:14 p.m. System on 8 a.m. Generated 4 to total 572 KWH. National Grid meter 307. Day 64: Friday, Nov. 2, 2007 Sunny. Generated 12 KWH. 5:05 p.m. National Grid 293. 10:35 a.m. Sunny. Sunrise 7:32, sunset 5:49. System on at 7:55 a.m. Generated 1 for 557, National Grid 301. Day 63: Thursday, Nov. 1, 2007 5:05 p.m. National Grid meter 295. 4:30 p.m. Generated 4 KWH. 10:30 a.m. I really am going to stop frequent readings, but I wanted to get the totals this morning. Here goes: A gray day; system on at 8:20 a.m., less than 1 KWH generated. 660:42 hours of operation, 552 KWH of electricity generated, 717 pounds of carbon dioxide pollution avoidance, National Grid meter 296. Day 62: Wednesday, Oct. 31, 2007 THIS MONTH's ELECTRIC BILL: $40.36 Generated 11 KWH today. Received the second National Grid bill since we turned on the photovoltaic system. We used 174 KWH from National Grid and the charge is $40.36. Last October we bought 477 KWH from National Grid. In addition to installing photo-voltaic we have reduced our use, primarily by not leaving the two computers on 24/7. I estimate the two together were using about 5 KWH daily (about 150 KWH a month) and we may have halved that to 75 a month. With two months of records in hand, I do not plan to continue extensive daily record keeping. I may post weekly usage for awhile. 5:10 p.m. National Grid meter 286. 4:30 p.m. 11 KWH generated today. 3:30 p.m. Sunny 10 KWH. 2:25 p.m. Generated 8 so far. The National Grid electricity bill came today, the second one since we turned on the photovoltaic system. We used 174 KWH and the charge is $40.36. Last October we bought 477 KWH from National Grid. In addition to installing photo-voltaic we have reduced our use, primarily by not leaving the two computers on 24/7. I estimate the two together were using about 5 KWH daily (about 150 KWH a month) and we may have halved that to 75 a month. 11:45 a.m. Generated 3 KWH so far today. 9:35 a.m. National Grid meter 294, system on at 7:50 but less than 1 KWH generated so far. 541 KWH generated in the first two months: On August 31, I turned this system on. Day 61: Tuesday, Oct. 30, 2007 12 KWH today! 5:00 p.m. 12 KWH! 2:05 p.m. Well, it's cranking 2,100 watts and we have 9 KWH so far today. 12:10 p.m. National Grid 290. 10:50 a.m. This is supposed to be a pretty decent day. We've been on since 7:45 and have generated 2 KWH. National Grid meter 292. Total system running time: 642:06, 531 KWH generated; CO2 pollution avoidance: 690 lbs. Day 60: Monday, Oct. 29, 2007 A nice day. 11 KWH. 5:15 p.m. 11 KWH; National Grid meter 265 2:10 p.m. A nice day 8 KWH so far. 10:55 a.m. System on 8:45, has generated 1 for 519 KWH since inception. National Grid meter at 290. Day 59: Sunday, Oct. 28, 2007 5:20 p.m. 8 KWH today; National Grid meter 282. 4:00 p.m. 7 KWH generated today. 1:10 p.m. 5 KWH. 10:45 a.m. System on at 7:47 and the sky is looking much better today. 2 KWH generated already for a total of 512. National Grid meter 284. Day 58: Saturday, Oct. 27, 2007 Gloomy today. We generated only 1 KWH for a total of 510 since system start-up. 6:10 p.m. National Grid meter 277. 3:30 p.m. We have generated 1 KW; I expect no more today. 10:20 a.m. A gloomy day. System on 8:30 but it has not yet generated a full KWH. To date, 509 have been generated since Aug. 31. National Grid meter 269. Day 57: Friday, Oct. 26, 2007 5 KWH today, more than I expected considering the shade of gray in the sky. 5:40 p.m. National Grid meter at 263. 4:15 p.m. 5 KWH -- more than I expected considering the shade of gray in the sky. 1:15 p.m. A gray day, no sense in watching this too closely. System came on at 7:45 and has generated 4 KWH so far today for a total of 508. 660 lbs of CO2 discharge avoided. National Grid meter 261. Day 56: Thursday, Oct. 25, 2007 5:00 p.m. Wonderful! We generated 12 KWH today. 257 on the National Grid meter (it ran backwards for 6 KWH.) 3:30 p.m. Great! 11 KWH. 10:30 a.m. Weather looks much better today. System on at 8:00 a.m., generated 1 for a total of 493 KWH. National Grid meter 263. Day 55: Wednesday, Oct. 24, 2007 Generated 2 KWH. 3:45 p.m. Gloomy and rainy today; no sense in reading it often. System on at 8:40, has generated 2 KWH so far. More is unlikely. National Grid meter 256. Day 54: Tuesday, Oct. 23, 2007 Overcast and rain. Just 4 KWH generated today. 4:20 p.m. We have had some rain. 3:00 p.m. Still overcast. Generated 4. 11:20 a.m. Overcast and a rainy day forecast. System on at 8:00 a.m. and has generated 1 KWH for a total of 487. National Grid meter 247. Our electricity is almost 2-for-1 from the sun. Day 53: Monday, Oct. 22, 2007 A nice, sunny day. Generated 12 KWH. 4:50 p.m. 12 KWH. 3:50 p.m. 12 KWH generated so far today. 2:45 p.m. 10 KWH but clouds are coming in from the west. 1:50 p.m. 8 KWH. 12:45 p.m. 6 KWH. 10:25 a.m. Looks like a nice day. System on at 7:50 a.m., generated 2 KWH, National Grid meter at 243. System started Aug. 31, has run 566:46 hours, generated 476 KWH, avoided polluting 618 lbs. of CO2, and peaked at 2,874-watt generation. Day 52: Sunday, Oct. 21, 2007 Generated 11 KWH. 6:10 p.m. National Grid meter 236 KWH. So we sold three KWH to the grid today. Actually, we stored it for free retrieval tonight. 5:20 p.m. Still 11 KWH. 3:30 p.m. Generated 11 KWH. 1:45 p.m. Generated 8 KWH. 9:55 a.m. System on at 7:50 a.m., generated 1 for a total of 464 KWH. This system has avoided discharge of 603 pounds of CO2 which otherwise would have been created to generate the electricity by conventional means. We've bought only 239 KWH from National Grid since we installed this system Aug. 31. We've used a total of 703 KWH since then, having generated 66 percent of it from the sun. Alternatively, you can say we cut our electric bill by two-thirds. Day 51: Saturday, Oct. 20, 2007 Generated 8 KWH today. 5:00 p.m. 8 KWH generated, National Grid meter 231. 4:05 p.m. 7 KWH generated. 12:10 p.m. 3 KWH generated. 9:00 a.m. System on at 7:40, total KWH 455 in 545:35 hours; 591 lbs. CO2 prevention, max output was 2874 watts. National Grid meter 229. Day 50: Friday, Oct. 19, 2007 Fog, overcast, rain: 4 KWH. 7 p.m. National Grid meter 223. 4:35 p.m. Light rain. Still 4 on the generation. 2:15 p.m. Generated 4. 9:45 a.m. Foggy. System on at 8:05. Generated 1 KWH for a total of 452. National Grid meter 220. Day 49: Thursday, Oct. 18, 2007 System on at 7:30; generated 5 KWH. 6:50 p.m. National Grid meter 214. 5:35 p.m. Still 5 KWH. 3:35 p.m. Generated 5 KWH. 12:55 p.m. Generated 3 KWH. 10:15 a.m. System on at 7:30; generated 1 KWH for total of 447. National Grid meter 215. Day 48: Wednesday, Oct. 17, 2007 Generated 9 KWH, total 446. 6:25 p.m. End-of-day National Grid meter reading 209. 4:55 p.m. 8 KWH, total 445. 3:15 p.m. 8 KWH. 2:05 p.m. 6 KWH generated for a total of 443. 12:55 p.m. On at 7:50 a.m., generated 4 KWH. Day 47: Tuesday, Oct. 16, 2007 6:10 p.m. National Grid meter 206. 3:40 p.m. A beautiful day, warm and sunny. Generated 12 KWH. 10:15 a.m. System on at 7:45 a.m., generated 1 KWH so far. National Grid meter at 212. Forecast is for a fair amount of sun. Since Aug. 31 we've generated 426 KWH and thereby avoided discharge of an estimated 533 pounds of CO2. Day 46: Monday, Oct. 15, 2007 Generated 7 KWH today. 5:05 p.m. Generated 7 KWH. National Grid meter 207. 9:45 a.m. System on at 7:50 a.m.. Total generation, 418 KWH; less than 1 so far today. National Grid meter 210. Day 45: Sunday, Oct. 14, 2007 Generated 10 KWH. Turned on the furnace today, switched the hot water to the furnace, and turned off the electric hot water heater. 3:50 p.m. We've generated 10 KWH. Confirmed that turn-on was 7:35, which seems early -- it must have been clear at sunup (7:08). This was the earliest turn-on since Oct. 6 when it came on at 7:20. On Oct. 9, not until 8:30. 11:05 a.m. System on at 7:35 a.m. and has generated 1 KWH. National Grid meter at 202. Since Aug. 31 the photovoltaic system has operated 487 hours 16 minutes, generated 409 KWH of electricity and avoided generation of 531 pounds of carbon dioxide. Day 44: Saturday, Oct. 13, 2007 Generated 10 KWH today, a pleasant surprise! Since Aug. 31 we've generated 67 percent of our electric use and bought only 33 percent from the electric company. 4:30 p.m. 10 KWH! Unlikely we will reach more. 3:25 p.m. Not a bad day after all -- we have 9 KWH so far. 9:25 a.m. 0 on the sun meter so far today, 398 total and 194 on the National Grid meter. Those numbers tell the story: add them and get the total amount of electricity we've consumed since 8/31/07 when they were turned on: 592 kilowatt hours. Now figure the percentages: we've bought 33 percent of it from the electric company and taken 67 percent of it from the sun. We've cut our electric bill by two-thirds! Day 43: Friday, Oct. 12, 2007 3:55 p.m. Ha! Prediction wrong! Sun came out and we have generated 6 KWH for a total of 398 since Aug. 31. N.G. meter down to 186. 10:20 a.m. Another gloomy day predicted. System came on at 8:15 but we've generated less than 1 kilowatt hour. National Grid meter at 187. Total generated so far, 392 KWH in 465:43 hours of service: 9.3 KWH per day on an average of 11 operating hours daily. We use an average of 17 KWH daily. Before we turned on the summer electric hot water heater, we were using 12 KWH daily. Our daily average generation hit the skids this week, which has been gloomy. With only 42 days in service, the average can't absorb days with only 1 or 2 generated without plunging. Estimated 509 pounds of carbon dioxide generation avoidance. Peak output, 2,874 watts. Day 42: Thursday, Oct. 11, 2007 A generally gloomy day. We generated only 1 KWH, our lowest ever. 4:45 p.m. Generated only 1 KWH. National Grid meter at 177 9:45 a.m. It's gray with a light rain falling. Less than 1 KWH so far. National Grid meter at 173. Since Aug. 31 we've generated 391 kilowatt hours of electricity in 456:10 hours of operation and reduced CO2 emissions by an estimated 508 pounds. The 456 hours is an average of about 11 a day that it is on. Day 41: Wednesday, Oct. 10, 2007 5:35 p.m. 11 KWH generated today. Nice, following the last few days. National Grid meter down to 165. 3:30 p.m. It's been quite sunny and we've hit 10 KWH and a peak generation of 2,670 watts. Noon. Anne reports that the National Grid meter is down to 168. 10:25 a.m. System on at 8:05. Gray earlier but getting sunny now. Have generated 1 KWH for a total of 381 since Aug. 31. National Grid meter at 170. Without the solar system I would have bought more than 500 KWH from them, instead of 170. Here are some additional data I took off the panel: Current generation level was 1,359 watts; max since start was 2,874. System has been on for 447 hours 18 minutes. An estimated 495 pounds of carbon dioxide creation was avoided by solar generation of the 381 KWH of electricity since start. Our billing rate was about 14 cents per KWH on the last bill so we have saved about $53.34 in 40 days -- $1.33 per day. Day 40: Tuesday, Oct. 9, 2007 A gray day. Generated 3 KWH. 6:30 p.m. System off so I cannot read it; National Grid meter at 158. 5:00 p.m. 3 KWH. 1:30 p.m. Generation still at 2 KWH. We've been doing laundry on this wet day and using the electric dryer (two loads through) so we checked the National Grid meter. It's at 155, so we've used 7 KWH since 9:45 -- the five on the National Grid meter and the two we generated. The laundry was cold-water, so that's not a factor here. Normal electric use would be about 3 KWH in four hours; we used 7 in a little less than four hours so the dryer may have been 4 KWH, or two per load. 12:15 p.m. Hey! We've generated 2 KWH! 9:45 a.m. Another gloomy day. System came on at 8:30 but generation so far is less than 1 KWH. National Grid meter at 150. Day 39: Monday, Oct. 8, 2007 A gloomy day. Generated 4 KWH. Tuesday. Total KWH generated is 377 with none on Tuesday so Monday's total must have been 4. 3:40 p.m. We have 3 KWH so far today but it is gray enough that I expect we will not reach 4. 10:50 a.m. Another overcast, rainy day. System came on at 7:50. Generated 1 for a total of 374 KWH. Back on Sept. 10 it was so gloomy that the system did not come on until 12:05. We only generated 2 KWH then; yesterday we made 3. Top generation was 14 on Sept. 5. Day 38: Sunday, Oct. 7, 2007 Overcast. 5:15 p.m. Generated 3 KWH today for a total of 373. National Grid meter at 122. 12:50 p.m. An overcast day and only 1 KWH generated so far today. System came on at 8:15 a.m. Day 37: Saturday, Oct. 6, 2007 5:20 p.m. Generated 10 KWH today. It's clouding and there's distant thunder so no more sun today. National Grid Meter is 109. 2:20 p.m. Generated 8, total 368 KWH. 9:30 a.m. System on at 7:20 a.m. Less than 1 KWH, total 360. National Grid meter 112 Day 36: Friday, Oct. 5, 2007 Generated 10 KWH today for a total of 360. 5:50 p.m. National Grid meter at 104. 3:50 p.m. Generated 9 KWH. 1:30 p.m. Partly sunny. Generated 7 KWH so far today. 9:20 a.m. System came on at 7:25 a.m. Generated less than 1 KWH today, 350 through yesterday. National Grid meter at 107. Day 35: Thursday, Oct. 4, 2007 The system came on at about 7:20 a.m. and generated 11 KWH for a total of 350. National Grid meter was 98 at 11:50 a.m. and 96 at 4:40 p.m. The solar installers were here working on the hot water system. Work interrupted taking readings and also updating the diary. Day 34: Wednesday, Oct. 3, 2007 6:20 p.m. Generated 10 KWH today. National Grid meter is 88. 5:10 p.m. It cleared up quite a bit. 10 KWH generated. 10:20 a.m. Generated 1 KWH. 9:45 a.m. Cloudy today. System came on at 7:35 but has generated less than 1 KWH. 8:10 a.m. National Grid meter at 93. Day 33: Tuesday, Oct. 2, 2007 Generated 13 KWH. Total generated to date: 329. Total pollution (CO2 discharge) avoidance: 427 pounds. Since installation we've generated just under 10 KWH a day. 9:30 p.m. I had time to do some calculations. Since installation we've generated just under 10 KWH a day. The new electric hot water heater (40 gallons, set at about 120 degrees) seems to be using about 5.5 KWH a day. That would be about 825 KWH for the 150 days the furnace may be off, or $144 to operate the electric water heater. This all started because I was getting $400 to $500 worth of fuel oil delivered in July when only the April to May period was used for heat. The rest of that oil was for hot water. There's always an October fill-up, too. Next year the furnace will be turned off completely in May. 6:10 p.m. Generated 13 KWH today, quite a surprise. Total generated to date: 329. Total pollution (CO2 discharge) avoidance: 427 pounds. National Grid meter at 85. System shut down just after I took the numbers. 4:00 p.m. Generated 12 KWH. 10:50 a.m. A little foggy early, then overcast, now partly sunny. System came on at 7:30. Have generated 2 KWH for a total of 318. National Grid meter was 89 at 9:25. Day 32: Monday, Oct. 1, 2007 The electric bill arrived today, the first since we have the solar installed. We bought 111 KWH during the nine days before the change and another 45 KWH during the twenty days following installation of the new meter. The KWH rate we pay dropped slightly however there is a fixed $16.21 per month "basic service" charge on both bills, so in a straight division of the bill by KWH it appears that the rate went up from last month's 17.2 cents to 24.4 cents. However when you subtract the fixed charge out of both bills and just divide the KWH charge by the number of KWH, we find our rate actually dropped, from 16.1 cents per KWH to 14.0 cents each. Last month's bill was $92.24. This one is $38.08. 5:05 p.m. Generated 11 KWH today for a total of 316 since system was installed. Pollution (CO2) avoidance: estimated 14 pounds. 12:10 p.m. Generated 4 KWH so far today. National Grid meter 84. 9:30 a.m. System on at 7:05, less than 1 KWH generated so far, total to date, 305. National Grid meter was 83 at 8:10. Day 31: Sunday, Sept. 30, 2007 Generally sunny. Generated 12 KWH today. 6:00 p.m. 12 KWH generated today. National Grid meter still at 73. 1:05 p.m. I don't know why I looked again so quickly, but it's up to 7 KWH generated so far today. 12:50 p.m. Generated 6 KWH. 10:30 a.m. Generally sunny. System on at about 7:15. Generated 2 for 295 KWH. National Grid meter was 73 at 10:15. Day 30: Saturday, Sept. 29, 2007 Sunny. A few days ago the 15-day forecast had no more sunny days but now, tomorrow and Monday are also supposed to be sunny. 5:45 p.m. Generated 13 KWH today for a total of 293 since Aug. 31. National Grid meter at 65. 4:50 p.m. 13 KWH. 9:15 a.m. System on at 7:15. Good forecast. Already generated 1 KWH for a total of 281. National Grid meter at 72. Our generation has avoided adding an estimated 365 pounds of CO2 to the air since Aug. 31. Day 29: Friday, Sept. 28, 2007 Overcast. 3:40 p.m. Generated 4 KWH for a total of 280. Sun generation avoided adding five pounds of CO2 to the air. National Grid meter at 63. 12:20 p.m. Overcast. 2 KWH generated for a total of 278. System came on at 7:15. 8:30 a.m. National Grid meter at 60. Day 28: Thursday, Sept. 27, 2007 Generated 8 KWH. 3:55 p.m. Thunderstorm starting. Generated 7 KWH. System now supporting electric hot water heater in summer months. It was installed today. Will use furnace in winter, as in the past. It was the $400-500 July oil bills that made me look at solar. Heat goes off in May so how much of those July oil bills were for hot water? Most. And they are followed by a fall fill-up in October. 11:45 a.m. Overcast and generated 2. System came on at 7:15. 8:50 a.m. Overcast. Generated 1 KWH for a total of 269. National Grid meter at 49. The system estimates 349 pounds of carbon dioxide have not been put into the air as a result of generating electricity by sun rather than fossil fuel. That's only a guesstimate -- we have no way of knowing what National Grid's electricity is fueled by. Excepting that we put sun-powered juice back into the grid when generating more than we use. It's probably based on a nationwide average of fuels used to generate electricity. The estimate here is that we don't dump 13 pounds of CO2 into the air daily, when we generate our average 10 KWH of electricity per day. I wonder how many 55-gallon drums it would take to hold 349 pounds of CO2. Day 27: Wednesday, Sept. 26, 2007 A little cloudy, then sunny, then it clouded up. 3:55 p.m. 11 KWH so far today. It's clouding up so that may be the top for the day. 12:30 p.m. Generated 5. 10:50 a.m. A little cloudy earlier but it's generally sunny now. System came on at about 7:10. We've generated 2 KWH for a total of 259. National Grid meter is up to 48. Day 26: Tuesday, Sept. 25, 2007 A sunny day, probably the last for some time. Generated 12 KWH. 5:00 p.m. National Grid meter down to 42 KWH. We've bought only 1.6 KWH a day since Aug. 31. We used to buy 15 a day. 4:40 p.m. 12 KWH generated today. 1:05 p.m. Generated 7 KWH. Clouds and thunderstorm expected tomorrow. AccuWeather is not predicting another sunny day like today until Oct. 8. Whatever we generate today will not be matched again until spring -- I would think March at best. But we will see. 11:45 a.m. Sunny today. System came on at 7:15 and we have generated 4 KWH for a total of 249 since Aug. 31. National Grid meter is up to 46. Day 25: Monday, Sept. 24, 2007 Sunny. Generated 12 KWH. 4:20 p.m. National Grid meter is down to 42. 2:00 p.m. Generated 9 KWH so far today. Output has hit 2,235 watts. 12:15 p.m. Generated 5 so far. National Grid meter at 47. 10:00 a.m. Sunny again. System on at about 7:15. Generated 1 KWH for a total of 234 since Aug. 31. We used the electric range more than usual last night and the National Grid meter is up to 50. Day 24: Sunday, Sept. 23, 2007 Generally sunny. 13 KWH today. National Grid meter down to 41. Since start-up on Aug. 31, we have generated 85 percent of the electricity we use. 4:40 p.m. Still at 13 KWH; National Grid meter down to 41. Since start-up on Aug. 31, we have generated 85 percent of the electricity we use. Our bill should be 15 percent of what it was. 4:10 p.m. 13 KWH. 2:00 p.m. Cranking 2,369 watts and generated 9 KWH. 8:05 a.m. Looks like a sunny day. System on at 7:15. National Grid meter at 48. Day 23: Saturday, Sept. 22, 2007 Generated 10 KWH, total 220 since start. That's about $38 off the electric bill. We've also started being more stingy with our use of electricity and may have saved $12 that way. $50 savings in 23 days! 4:30 p.m. Generated 10 KWH. It's unlikely we will generate more. 2:40 p.m. Forgot to check total generated to date so I looked again. Generated 8 today for a total of 218 since start on Aug. 31. 2:20 p.m. System came on at 7:00 a.m.; generated 7 KWH so far today. National Grid meter was at 49 when we looked at about 10 a.m. It was overcast early, then cleared to sunny. Day 22: Friday, Sept. 21, 2007 Generated 10 KWH today. Overcast at first, partly cloudy later. 6:20 p.m. Still 10 KWH generated today. National Grid meter down to 43. 5:20 p.m. 10 KWH. 2:00 p.m. Generated 7 KWH. Partly cloudy. 12:55 p.m. Generated 5 KWH. Now only partly sunny. 10:50 a.m. Generated 2 KWH. Generally sunny now. I noticed at 10:10 that it had cleared enough to see shadows. 8:50 a.m. Overcast -- not gray but white. The forecasts say sunny. Weather radar shows a mass of something coming in. National Grid meter is 47 -- down two from yesterday morning. We generated 12 KWH then so we must have used only 10. There is no battery storage in this system, the electric grid is our storage. Day 21: Thursday, Sept. 20, 2007 Sunny. 5:00 p.m. Generated 12 KWH today. 4:00 p.m. Generated 11 KWH. 1:55 p.m. Generated 8 KWH. 12:25 p.m. Sunny. Generated 5 KWH so far. 9:45 a.m. System turned on at 7:10. Forecasts are sunny but not as strong as yesterday. 1 KWH so far. National Grid meter at 49. Day 20: Wednesday, Sept. 19, 2007 A clear sunny day and we generated 13 KWH driving the National Grid meter down from 53 in the morning to 44 late in the day. I was able to check about every hour today and learned some interesting things. System came on at 7:10 and by 10:10 had generated one KWH. I don't know when that was reached. From 10:10 to 1:10 it generated two KWH per hour: From 1:10 to 2:15 it generated three KWH and from 2:15 to 3:15, two. From 3:15 to 5:50 it generated only one KWH. The collectors are partly shaded in the afternoon. 5:50 p.m. 13 KWH generated today. National Grid meter has gone down to 44. 5:20 p.m. 13 KWH. 4:20 p.m. 13 KWH. 3:15 p.m. 12 KWH. 2:45 p.m. 11 KWH generated today and National Grid meter down to 45. 2:15 p.m. 10 KWH generated. 1:40 p.m. 9 KWH generated; National Grid meter is down to 47. 1:10 p.m. 7 KWH so far today. 12:10 p.m. Generated 5. Seems to be 2 per hour; I will have to be sure to check a little after the hour each hour today. Clear sky: This is a peak generating day. National Grid meter is down to 50. 11:05 a.m. Generated 3 KWH. 10:10 a.m. Generated 1 KWH. 8:30 a.m. Forecast is sunny. System came on at 7:10. National Grid meter is at 53, the same as last Wednesday. We've generated less than a KWH today but a total of 175 since the system start-up on August 31. Day 19: Tuesday, Sept. 18, 2007 Sunny. 6:20 p.m. Still 13 KWH for the day. It must be 13 and a large fraction of the 14th. I thought for sure we would get 14 today. 3:35 p.m. Really cooking! -- 13 KWH. Dare I hope for 15, a record on this system? 1:50 p.m. We are cooking! -- 9 KWH so far. 12:35 p.m. Sunny. Generated 6 KWH so far today. 9:15 a.m. A little cloudy but it is supposed to get better. System on at 7:15, generated 1 KWH already for a total of 163 since system start. National Grid meter at 56. Day 18: Monday, Sept. 17, 2007 Sunny but turning colder. Generated 14 KWH today for a total of 162 since installation. 5:00 p.m. 13 KWH today. Sky still clear. If it's 13 plus a large fraction, we should hit 14 today. 2:45 p.m. This appears from the shadows to be peak sun time -- it is dead straight to the barn. There is no shade from the neighbor's tree, only from the few small clouds. We have generated 11 KWH today and are now flopping between 1,800 and 2,200 watts on the output meter. 2:15 p.m. We have generated 10 KWH and have hit 2,800 watts output. Sun is not yet aligned straight to the barn. Another 15 minutes maybe. That should be peak output. 12:00 noon. 5 KWH so far and it has pumped as high as 2,500 watts this morning. We could hit 12 today, maybe even more. 9:15 a.m. A sunny day is forecast and the sky is clear. System on at 7:05 a.m. and 1 KWH generated. National Grid meter at 59. Angle of the sun is significant here, and the solar collectors are on a roof facing generally south. Therefore, they do not crank juice heavily in the morning. I think the most direct exposure occurs between 1 and 2 p.m. Day 17: Sunday, Sept. 16, 2007 Sunny for awhile but turned mostly cloudy in late afternoon. Generated 9 KWH today for a total of 149 since Aug. 31. 4:00 p.m. 9 KWH generated today. Checked the time and found it went on at 7:05 today. 1:40 p.m. It was sunny for awhile but has turned mostly cloudy. Generated 7 KWH today for a total of 147. 7:00 a.m. National grid meter at 56. 6:30 a.m. I must leave before the system comes on and will be gone until early afternoon. The forecast is sunny but the sun won't be up for another 8 minutes, so who knows? Day 16: Saturday, Sept. 15, 2007 Overcast to mostly cloudy today. 5:25 p.m. Generated 7 KWH today. 3:00 p.m. Generated 7 KWH so far today. 11:15 a.m. Generated 1 KWH. Skies improving. 9:30 a.m. Overcast and we have had some rain. More expected. System has been on since a little before 8 but has not yet generated a full KWH. Day 15: Friday, Sept. 14, 2007 Mostly cloudy but generally bright. Generated 8 KWH. 3:15 p.m. Generated 7 KWH today. I have an engagement and won't be back until after dark when the system is down, so we won't know today's total until I push buttons tomorrow. 12:40 p.m. Cranking at 1,900 watts and generated 4 KWH so far today. It hit 2,400 watts sometime before I checked. It's generally overcast, however. 9:55 a.m. Overcast and a poor forecast. System came on at 7 a.m. and has generated 1 KWH. National Grid meter at 53 - same as Wednesday. We turned the solar system on two weeks ago today at about 9:15 a.m. so we have bought an average of 3.8 KWH a day on top of the 8.9 KWH a day that we've generated from the sun: We've used 12.7 KWH daily, on average. When we started this venture we left two computers on 24/7, which we do not do now. That was costing 2 to 4 KWH daily. A KWH, by-the-way, cost about 17.5 cents on my last electric bill. We've generally used about 15 a day for electric bills of $75 to $80 a month. Turning off the computers except when in use is saving us $15.66 a month, the solar system has been producing at $46.73 a month, and we are buying at $19.95 a month from National Grid. That adds up to an $82.34 electric bill but we pay less than $20. We realize, of course, that we will generate less during winter with shorter days and the sun lower in the sky. Day 14: Thursday, Sept. 13, 2007 Generated 10 KWH today; system has generated a total of 125 since turn-on -- $21.87 at the price I pay. National Grid meter went down to 47 before starting back up in evening: we are generating more than two-thirds of our use. 6:30 p.m. 10 KWH today. Little likelihood of more before it shuts down. National Grid meter is 48; it was 47 when Anne got home at about 5:30. 3:45 p.m. We are up to 10 KWH. 1:25 p.m. Generated 6 KWH so far today but the sky has turned to mostly cloudy. 11:15 a.m. We are cranking at 1,875 watts and have produced 3 KWH so far today for a total of 118 in less than two weeks. Today's forecast is mostly sunny. I hope to generate 12 to 14 KWH today. 10:30 a.m. System on at 7:05 a.m. and 2 KWH generated. National Grid meter at 53. Day 13: Wednesday, Sept. 12, 2007 Somewhat better sun today: 5:45 p.m. 8 KWH today. 4:15 p.m. 7 KWH today. 3:30 p.m. Sky better-- partly sunny. 6 KWH. 12:30 p.m. Forecast is a lie. It's mostly cloudy. Generated 4 KWH. 10:00 a.m. Forecast is sunny to partly sunny today. System came on about 8 a.m. and we have generated 1 KWH today for a total of 108 since 8/31/07. National Grid meter was 48 when Anne looked at about 8. Day 12: Tuesday, Sept. 11, 2007 Overcast and rainstorms. 5:10 p.m. 2 KWH generated. 3:45 p.m. We reached 1 KWH at some time since 11. 11:00 a.m. System turned on at 9:52 a.m. Less than 1 KWH generated so far but total to date is 105 so we must have generated 2 yesterday. National Grid meter at 42. 9:00 a.m. Rainy. System is not on so I am unable to confirm yesterday's closing numbers. National Grid meter is at 41. Day 11: Monday, Sept. 10, 2007 A gloomy day. We generated 2 KWH and ran the National Grid meter up to 33. 5:15 p.m. Still only 1 KWH today. Grid meter at 33. It's gloomy out. 4:15 p.m. Generated only 1 so far, which I found at maybe 3 p.m. but forgot to note the time. 1:25 p.m. Overcast today. System finally came on at about 12:05. 0 KWH generated so far. National Grid meter is at 31. We must have generated the 4th KWH yesterday because the total generated at 103 but none today. 10:55 a.m. System does not yet have enough light to turn on. 8:20 a.m. A gray day and there is not yet enough light to turn on the system. National Grid meter is 28 -- we stewed a bushel of tomatoes yesterday and left the soup simmering overnight, all on the electric stove. Day 10: Sunday, Sept. 9, 2007 A gray day. We generated only 4 KWH today. 5:15 p.m. Dark sky and thunder. System shut itself down as I was raising the lid to take a reading. Not enough light. I'll be surprised if we generated that 4th KWH today. 4:10 p.m. Generated only 3 so far but Grid's meter is still 12. 10:00 a.m. Rain overnight, gray and thundering in the morning. National Grid meter at 12. We have generated 1 KWH today for a total of 100. Day 9: Saturday, Sept. 8, 2007 A gray day -- rain threatened but failed to materialize. 5:50 p.m. Generated 7 KWH today for a total of 99. National Grid meter still 5. 2:30 p.m. It's generally overcast with occasionally enough sun to see a shadow. Generated 5 KWH, National Grid meter down to 5. Three days ago we had generated 10 by 2:25 p.m. That was our best day so far -- 14 KWH. 8:30 a.m. National Grid meter is 7 KWH this morning. It's gray and the forecast is mostly cloudy and chance of thunderstorms. It will be interesting to see what we generate today. Day 8: Friday, Sept. 7, 2007 Partly cloudy today. 7:00 p.m. Generated 11 KWH today for a total of 92 in eight days. National Grid meter is at zero: we owe them nothing. 3:05 p.m. Generated 9 KWH so far today and the National Grid meter is down to 99999 -- that's one below zero and a credit balance with the electric company at this time. 1:40 p.m. Generated 7 KWH today and meter is down to 1. It's partly cloudy. Peak generating time is between noon and about 2 or 2:30 p.m. when the sun is lined up straight to the garage. We're doing much better than a week ago because we now generally leave the computers off whereas they used to be on 24/7. These updates are from the laptop running on a battery; I will plug it in and recharge it later today. 12:15 p.m. It's fairly bright and we've generated 4 KWH so far today; meter is down to 3. 9:10 a.m. I turned the system on just a week ago. The power company's new meter was at zero. This morning it reads 6 kilowatt hours. I'll pay them about $1.05 for that. We've generated 81 KWH since then, so we have used 87, which would cost about $15.22 to buy from National Grid. My savings this week is $14.06. We supplied 93 percent of our electrical need this week. Today's forecast is hot, humid and partly cloudy. Day 7: Thursday, Sept. 6, 2007 Generated 12 KWH today. National Grid's meter was at 2 KWH in the evening, after running for nearly seven days. We had high, thin clouds much of the day. 10:15 p.m. National Grid meter at 2. 6:30 p.m. Generated 12 KWH today and Grid's meter is still 0. 3:40 p.m. Surprise! National Grid's meter is down to ZERO! We've generated everything we've used since Friday morning. 11 KWH so far today. 12:35 p.m. Clouds are thin and we've generated 5 KWH, peaking at 1,950 watts. The National Grid meter is up to 4 KWH. I've done two loads in the washer. 10:00 a.m. Quite a few clouds today. Generating only 900 watts but we have hit 1 KWH for the day. The National Grid meter is up to 6, from 2 last night. That indicates a noticeable saving by turning both the computers off overnight. We are now generally leaving them off for prolonged periods. I will do a laundry today; have not laundered since we started using this system. Do not know if I will be able to determine laundry impact. We don't use the dryer, excepting to tumble a little, unless it is rainy. Day 6: Wednesday, Sept. 5, 2007 Generated 14 KWH today, total of 69 in the six days since we turned it on. The National Grid meter read 2 at dark and had been as low as 1. Peak generation today: 2,317 watts. Only a few clouds, then mostly thin. 5:30 p.m. Shazam! We hit 14 KWH today, our best yet! Total we're buying from National Grid same period: 1 KWH. I'm impressed: We've generated 98.6 percent of our need. Of course we will not do as well in winter when sun is low and days are short, but we will do better in May and June. 4:15 p.m. We've generated 13 KWH today and the meter we pay on is down to 1 but we are only generating 400 watts because of sun angle, tree shade and a little cloud cover so I doubt we will get that 14th KWH today. 2:25 p.m. The sun is nearly in alignment with the solar grid but there are a few thin clouds. Still cranking at 2,200 watts or a little more. Today's generation is up to 10 KWH and the meter we pay on is down to 3. That's 3 KWH in five days, folks. We use about 12 a day so we're nearly supplying our need. 1 2:55 p.m. Now cranking 2,200 watts; generated 7 KWH so far today; pay meter is down to 6. Shadow from roof indicates the sun is not yet aimed dead-on straight at the collector panels. When that happens I believe we would have max generation excepting for any clouds. Neighboring tree shades it a little in the afternoon; don't know if that will kick in before or after the high generation point. 11:05 a.m. System turned itself on at about 6:57 a.m. Mostly sunny now. We are generating about 1,800 watts, have generated 3 KWH today and the meter we pay on is down to 9. 8:15 a.m. Meter we pay on is at 10, the same as yesterday morning. We generated just as much as we used! Only a few clouds. Day 5: Tuesday, Sept. 4, 2007 12 KWH today, which was partly cloudy. Generated 8 by 1:45 p.m. Total of 55 KWH generated since Friday morning. Net buy has been 10 so we've used 65 or average of 13 KWH a day. Leaving the two computers on overnight seems to use 2. Day 4: Monday, Sept. 3, 2007 13 KWH generated today, 43 since Friday morning. Clear and sunny in the morning, partly cloudy and sometimes gray in the afternoon. The meter we pay on shot up from 3 last night to 11 this morning. By mid-afternoon it had gone down to 4 and now it has gone up to 5. I suppose that the 13 KWH generated yesterday and today will be the most we will see until the days are longer in spring, since it was sunny all day yesterday and days are now getting shorter. The system started generating today a little before 7 a.m. and was cranking less than 100 watts at 7 p.m. It generates a little over 2,400 watts in clear, sunny conditions. Day 3: Sunday, Sept. 2, 2007 13 KWH today. Sunny and cloudless. Day 2: Saturday, Sept. 1, 2007 Generated 11 KWH. Mostly sunny. Day 1: Friday, Aug. 31, 2007 Turned photovoltaic system on at 9:15 a.m. and generated 6 KWH today. Morning was overcast, then mostly sunny.
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