Monday, November 9, 2009

New Season of "Living with Ed" ???

I just saw Living with Ed come up on my TV selection screens, and noticed an episode date of 2009. Yikes. They are back at it.

Living with Ed
BRAND NEW Episodes on Planet Green TV
Wednesdays at 9PM EST
Repeat on Mondays, 9PM PST

Saturday, October 10, 2009

Final bill for the "on-peak" time of use

Through the October bill for PG and E, we have a total of $78.25 in credit. Last year, we had $45.16 at this point. We go into the Off-peak mode at the end of October.

Friday, September 11, 2009

Sept Billing Period

Sept 2009 we used 92 KWh for credit of $9.19, bringing our total for the billing year beginning June 2009 to 205 KWh used, and $71.46 (credit). Last year in Sept we had $8.39 in credit with a use of 83 KWh, a total of 278 KWh used and $36.16 (credit).

Our yearly use for 2009 seems to be lower by 73 KWh, even with the addition of our pond pump running daily. Our credit for the year starting in June is running $35.30 above last year’s total through this Sept.

Thursday, September 3, 2009

update Nearing 15,000 KWhs Produced

It happend a bit sooner than I expected. We are now at 15,148 KWh produced. If we had the correct orientation all along I wonder what our total would have been now? I could figure it out, but it would not change anything.

Wednesday, August 26, 2009

Taking a Dim View of Solar Energy

A Newsweek article suggests that utility companies may begin to fight the incentive programs now in place as their energy shares decrease in the wake of huge increases in roof-top energy production, suggesting that “So far, they're getting vastly outpaced by the decentralized rooftop approach. According to the Interstate Renewable Energy Council's 2006-08 count, consumers added 522 megawatts to the grid; whereas utility generated sites added just 96 megawatts.” The increase is attributed in part to subsidies and also to lowering prices overall of solar panels.

It goes on to say “The disparity has utilities worried about loosing (sic) their grip on the country's energy industry, and the $130 billion residential electricity market. In some cases, utilities are actually taking direct steps to thwart rooftop solar. Two weeks ago in Colorado, the state's biggest utility, Xcel, tried passing a surcharge on homes and businesses using rooftop solar power. The rate hike would've generated $180 million, $55 million of which was slated to help fund Xcel's newest coal-fired power plant, the Comanche Unit 3, due to come online this fall. The public went ballistic, and with pressure from Democratic Gov. Bill Ritter, the proposal was eventually shelved.”

Monday, August 24, 2009

Is gas still too cheap?

It must be for some.

For others I am sure high prices lead to scrimping at times to be able to fill the tank when those bargain prices under $3.00 a gallon surface. I drive a Prius, and I am very aware of my gas use. I get oddly upset when my mileage on any given tank drops below 50 MPG (my lifetime mpg average). And even with mostly shorter trips, I can usually have 50 MPG around town in summer.

Then I see an SUV type vehicle in the parking lot of our local Trader Joe’s food store. I can hear the motor running, and I see a person in the passenger side front seat, obviously listening to a favorite song on the radio. This is nothing I have not seen before even with prices closer to $5.00 a gallon briefly last summer. This one is different though.

For one thing, it is only around 80 degrees at barely 10 am. Sure it may be hotter later, but this is still basically a nice cool morning for summer around here. Surely it is not warm enough to waste gas with the AC on. But, I figure maybe the person has some sort of infirmity requiring cooler temperatures than a normal person. Then I see the ultimate irony of the situation. The SUV’s rear passenger windows are both down. What is the point of that?

As I loaded my own groceries, the driver of the SUV came to load theirs. I figured he will see the rear windows are down, and scold his passenger for messing around with the windows. No. This did not happen. He simply opened up the back, loaded the bags in, and drove off with the rear windows down. Why is that so odd? I mean, I drive around with my windows down too. The difference is that my AC is not on when I do so.

Even when gas was closer to $5.00 a gallon last summer, I saw people running their AC while the car was parked. I remember one time there was a beautiful young lady in the passenger seat. While I sat nearby with my windows down and wind blowing through, the young male driver came over with his hands full of icy refreshments from two different stores. I can understand why he allowed her to sit in the car running AC on a day it was not that hot out. He had other things on his mind and no doubt wanted to impress her.

At least she had the windows up.

Saturday, August 15, 2009

August 2009 PG and E unbilled credits in-

Well, the end of July was mostly in the mid 90’s to low 100’s, similar to how it was last year. Last year we used 132 KWh with an unbilled credit of only $2.57. It was a pretty hot month last year also, but to me it seems we ran the AC more this year than last. I think we must have increased efficiency other places. This year, we used 116 KWh- so right away; we had an improvement of 16 KWh in use. Plus, our unbilled credit for the month is $14.61. Our total unbilled credit for 2009 goes to $62.27. The rest of summer is looking pretty good at this point. Our total for last year summer production was only $45.00 through October.

Wednesday, July 22, 2009

Nearing 15,000 KWhs Produced

In a couple of months our PV array production should pass 15,000 KWh in around five years. Of course, most of that is with the inferior southeast orientation, but it is still pretty good even at that.

Monday, July 20, 2009

Let the consumer beware. . .

This thing about having to pay to have our panels moved still ticks me off. So, I went back to my contractor and showed him how big the difference in production was between the old location and the new, and asked him if- since he had mentioned that ‘we usually install them on the southwest side if it is available’- if he could help us out a bit in the fee to move them. To us, it seemed like paying to move them was rewarding them for making a mistake in the location in the initial installation.

Nope. They are not liable for placement of the panels being inferior to another placement. He claimed that the industry standards only suggest that the companies install panels in a generally southerly position within a range of degrees of direct south. And, they were within that range in the initial installation.

So, BEWARE consumers. Make sure that the location of your panels is correct and will maximize your production from the start. Most solar contractors now have access to equipment that can tell you the maximum exposure for your installation. Go with one of those. If you have a contractor without this equipment, even if they are the low bid- Get a new contractor. They are only guessing. And with your system costing as much as they can cost it is worth it to have them where you will get the maximum exposure to get a faster payback.

Saturday, July 11, 2009

The July 2009 PG and E bill is in

Well, for our first full two month total credit for 2009, we have hit $47.66 which is just about what our total unbilled credit was through all of last year. This is looking pretty good. We did have a bit of AC use last month so our total electricity use is up to 10 Kilowatt Hours for July. Of course, putting that with our 13 KWh credit from June, we still have a 3 KWh credit over the first two months of this billing year. The 10 KWh use for July 2009 compares to a relatively high 63 KWh in July of 2008. It is amazing what moving those panels has done.

Oh, and the natural gas portion of the bill is pretty good also. For July, our gas bill was only $3.93 for 2 therms for the month. That is about equal number of therms compared to last year.

Monday, July 6, 2009

Cleaning your Solar Panels to get the maximum production

How many times have I seen Ed Begley Jr. hop up on his roof and clean his solar panels as if he was standing on solid ground without a care in the world? Too many times- actually, this is more a comment on how often the show “Living with Ed” is re-run. I guess a new season is not in the works? Too bad: I guess we will have to live with the limited series it was. Now, getting back to cleaning the panels, what do you do if you are not Ed Begley Jr., or do not at least have his “non-fear” of roofs?

I have already mentioned that a dirty panel can cut as much as 7% annually from your production. It would seem that you should try to find a way to get at least some of the dirt and grime off. There may be a way at “Real Goods”. This is a solution that comes pre-mixed in an applicator bottle. You simply connect it to a hose, get as close to your panels as you can without taking the inevitable plunge off the roof- and spray it on your panels as if you are applying fertilizer to your lawn through a hose end sprayer. That is basically it. You spray the surfactants on, and let it soak into the crud for a few minutes. Then you switch the sprayer to fresh water and rinse the dirty suds away. I am sure it would be better to actually have a brush to physically wash the heavier stuff away, but this is a pretty easy alternative to that heavier job. I am not 100% sure how it has worked yet, but the panels did appear to be cleaner after the treatment. Time and the next PG and E statement will tell if it has helped. It could at least work as in interim solution until you can locate someone else to do it in return of a six-pack of their favorite beer.

Monday, June 29, 2009

Prius at 6 years old

With my 2004 Prius approaching 50,000 miles- I guess I do not drive much- I am still averaging just less than 50 miles per gallon through all seasons, and all driving types and road conditions. That beats the re-configured EPA mileage by close to 4 miles per gallon. From what I have seen, the 2010 is a lot more of a car with a lot more bells and whistles than prior generations. I would love to try out the new generation Prius for 2010, but my 2004 has quite a bit left in it and I feel lucky to have what I have at this point.

Saturday, June 13, 2009

Best June PV production ever!!!

I knew our alteration to the panel orientation would work out. Of course, we had the usual monthly fees that they charge everyone no matter what. Those usually range between $5 and $6 dollars a month, and go towards the yearly total when they calculate the true-up bill at the end of the year. Here is the good part.

June of 2008, we had started out with a surplus for the month of $17.34 and had a use of 14 KWh for the month that we did not produce.

For June of 2009, we had a surplus of $25.07, and our total electricity used was -13 KWh. Yep, that is negative 13 KWh.

This is the first time we have ever created more electricity than we have used. The usual surplus we have had was based on the differential charges for peak compared to non-peak. That is amazing. And, it really makes me a bit angrier at our original solar company for putting our panels facing an inferior direction for the first few years.

Wednesday, June 10, 2009

Cooler June in progress- And a Prius mention

I guess this has its trade-offs. On the one hand, we are not making as much power on the partly cloudy days we have had the last week or so. But, it is staying cooler and there is not as much need to run the AC. We seldom run it much anyway, so all in all, I would rather make more electricity.

And, I see that some Toyota dealers are starting to get the 2010 Prius in: not mine, but that is OK. I would like to see one close up since this model includes some body changes and a more luxurious car-like interior. I am somewhat bummed that I cannot get one. I purchased the first Prius in my town in 2001, and the first one that was sold of the new body type 2004. Oh well. It is the economy. Maybe someday.

Wednesday, May 20, 2009

World Community Grid Clean Energy Project

You might have heard of the SETI@Home project which for the last ten years has used internet connected computers to search for signals with other worldly origins. That project has evolved over time, and now its success has spawned countless other projects that either search for things out there in the universe, track near earth objects, model climate change, look for cures to diseases, and others. This is possible due to a program called the Berkeley Open Interface for Network Computing, aka BOINC.

The original Seti@Home site is here if you want-

The BOINC site is here

You may ask what this all has to do with this blog? Well, if you go directly to a site called World Community Grid you will be able to download a version of BOINC to process data for the Clean Energy Project which is looking for the next generation of materials to use in cheaper solar panels. Of course, there are other projects you can support too. I will just concentrate on the Clean Energy one because it relates to the subject of this blog.

From the World Community Grid Clean Energy Project page, “The mission of the Clean Energy Project is to find new materials for the next generation of solar cells and later, energy storage devices. By harnessing the immense power of World Community Grid, researchers can calculate the electronic properties of tens of thousands of organic materials – many more than could ever be tested in a lab – and determine which candidates are most promising for developing affordable solar energy technology.”

If you are not familiar with the concept of network computing, once you have downloaded BOINC and chosen a project, your computer will download segments of data to process. This entire process will be done in the background as you do other things on your computer. When a segment is complete, your computer will upload the results and request more data to process. You can do as little or as much as you like, and designate your projects as you want. If you have more than one project, BOINC will distribute the computer time between them, again in the background.

Read more about the Clean Energy Project here at Green-Energy_News.

Thursday, May 14, 2009

Cost Comparison of PV Array 2007-2008

The 2008 True-up bill has been calculated for our electricity use. It is higher than last year, as anticipated. I think this is due to the pond pump running extra for a few months. And we have been home more this year. The pump is bound to be a continuing factor, but since we are now generating more each day, it may not make that much difference in the long run.

Our electricity cost has gone up from 4 cents per KWh in 2007, to 5 cents per KWh in 2008. This is based on increase use, and potentially a bit lower production due to the system being down for a few days to move the panels. The base rate for residential customers around here is around 15 cents per KWh.

In 2007, our total cost for electricity including all fees and taxes was $90.39. The total cost for electricity use that we did not generate was $17.78.

In 2008, our total bill for the year was $125.36 and of that $19.95 was for electricity we used but did not generate.

Tuesday, May 12, 2009

The Cleaning and Maintenance of PV Panels and System

One thing that is great about a PV System is that it requires almost no work to get the PV energy. Once it is installed, as long as you do not have to shut it down and move it to another side of the house, you should be OK for a long time. Most of the inverters I have seen have a lengthy warrantee. The panels themselves should outlive the longest investment payback. Most of them are guaranteed for twenty years. I know of panels near here that have been in use longer than twenty years, and are still producing close to what they did initially. Of course, in that same time replacement panels have made real gains in power output and efficiencies. Aside from the panel move earlier this year, we have only had one time our system was “down” for any problems, and that was for a simple part replacement for our inverter. That leaves only one real issue that I have been concerned about, cleaning the panels.

At least once a year, your panels could benefit from a good cleaning, especially if you are in an area that has a lot of dust or windblown pollen. This stuff can get stuck to the panels fairly easily, and although a lot of it is washed away by rain that happens in a time of year you are not really thinking much about production. Therefore, at least once a year, you need to think about cleaning the panels. If you are Ed Begley Jr. or otherwise do not have a problem climbing all over your roof at least once a year, or you have relatively easy access to the panels from the ground, you should have no problems doing your own cleaning. If you fear heights, or simply are older than Ed and your days of roof running are or should be over, what are you going to do?

After the first year of so our panels were up, our neighbor volunteered to clean the panels for us. That was great. It only cost us a six-pack. But, that is not the sort of thing we feel right about asking for repeat service the next year, or the next. I have asked a couple of solar installers in the area for their advice. They either say they do not bother cleaning their own panels, so I should not worry about cleaning mine. Or they say I could try a window washer service. I have not called one yet. Usually my experience asking a company to work outside their specified qualifications has not been good. So, when we moved our array recently, I asked the guys on the roof if they would be interested in making a bit extra money cleaning my panels. They seemed to want to do it when they were here. They told me to call them so we could arrange it. I called. I stopped by the place of business and left a message. I called again. I stopped by the place of business again and talked to the manager to ask if it was appropriate for me to ask. He said as far as he knew, it was something they could arrange to do, or if I wanted, I could contact his installer directly to ask him. I asked the manager to have the installer contact me. That was the last I have heard anything from them.

It seems to me there is a growing demand out there, or there could be a growing demand- for a service company that specializes in PV Systems maintenance. I am not quite up to getting up there and cleaning the panels the right way. The guys who could are missing an opportunity. Or, hopefully they are busy putting in more systems and just can’t get back to me. The thing is, it either forces me to live with dirty panels or to try to do it myself. Either way, the panels are not going to be as clean as they should be. And we will lose a certain amount of production. How much, and is it worth worrying about?

It is odd that I now know the answer to this. I have looked on the internet from time to time trying to find out how dirty PV panels impact production. I have not found it. Maybe I did not know the right terms to search for. What is the answer? What is funny about this is that earlier today, I went out to just hose off my panels. I thought that would help a little anyway. But as I said, it is not a complete cleaning, and there is still residual dirt there blocking my production a bit. I will check later to see if I had much gain over previous days.
Just now, I received a letter in the mail from a person who is doing PV system maintenance in our area. I do not know the cost yet, but he does PV panel cleaning, system module maintenance, system performance overall testing, warrantee troubleshooting and repairs, and will install a security system on the modules. This is just what I had been talking about earlier.

Oh, and the answer for how much dirty panels can cost you come from a study done by PV USA in Davis, Ca. They claim that after a dry rainy season dirty panels can impact your performance by as much as 7%. That seems pretty close to what I have seen here actually. Prior to my neighbor cleaning our panels, we were producing a bit over 9 Kilowatt hours a day. After cleaning, our production went up to a bit over 10 kilowatt hours. I guess it would be up to the individual owner to determine how clean is clean enough. And also it depends on the price of the service. I may call for the free estimate anyway.

Wednesday, May 6, 2009

All solar panels need is the sun- and the correct orientation for your area

Location is everything in placement of solar panels. Last year, we would be lucky if we were producing a couple of hundred watts by 3 PM while they were pointed to the southeast. What numbskull decided to put our panels on the southeast side originally? I want credit for those lost years of production, not to mention the more than a thousand bucks it cost to move the array. Now with the array towards the southwest, today at 6 PM we were still producing a bit over 1,000 watts. For the majority of our high cost time between noon and six, we will be in maximum production. In fact, at noon the production is 1,300 watts. So, we could be making between 7.5 to 8.5 kilowatt hours during the expensive pay back hours. Last year, we were lucky to get a total of 8.5 to 9.5 kilowatt hours in a good day, and since the sun was for the most part off of them around by 3 PM, only three hours of that was in the on-peak hours.

Monday, May 4, 2009

Here comes the sun- Not

Well, as of the first of the month, we are back on the prime time schedule for rate E7. So, after noon and prior to 6 PM, we should be making extra credit at the higher rate mentioned before. If only it was true. It is not sunny at all here, and has not been since the start of the month. I know we need rain, but the little amount we are now getting is not really going to help anyone- and it is hurting us. Beware those who want to go the way of trying to be more green. Things like this- or mileage decreasing on many short trips, etc, did not used to matter to me. Now, I worry about losing any ground to the weather, or to the tires being wrong, or to other things I may not have thought of yet. We need rain, but the time for that is past. Let there be SUN!

Monday, April 20, 2009

Prius again

I have now had my 2004 Prius for five years. Recently, my MPG has tanked a bit due in part to my tire change of a couple of years ago, and to the fact that my daily trips are much shorter than they used to be. So I was pleased over this last weekend to see overall MPG of 51 around town, and followed by almost 54 for a freeway trip to Santa Cruz. So the car still has decent MPG in it, and maybe those tires are finally broken in. MPG on recent occasions has been in the higher 40’s around town and in the low 40’s for freeway trips. Of course, this improvement on the freeway may also be related to just slowing down a bit from 70 mph to between 60 and 65 mph max. You would not think that would make such a difference, but it sure can on a long trip. Tires and proper inflation make a difference. Speed and time of year also make a difference.

Thursday, April 16, 2009

Solar update

Last billing month we had shut down the pond pump to run only 12 hours a day, and this month that is reflected in our new lower charge for electricity, as expected. For March, our unbilled charge was $43.70. For April, it had dropped to $15.16. That is just about $6 more than the previous year, but it is not good enough for us. We already dropped the run-time to 6 hours a day, and so far that is still keeping the water clear enough. But, the damage has been done to this year’s stats. We are already over $100.00 for the year, with one more month to go in the billing year. Last year at this point, we were at $75 total for the year. For the year, our total energy use is 2,305 Kilowatt hours, or about $.0437 per kilowatt hour. That is still pretty good since our base rate for residential use in this area is around $.15 per kilowatt hour.

Monday, March 30, 2009

Switching to the Prius

I have had my current Prius since late in 2003. Since then, my overall MPG figures are like this:

Overall Average MPG (calc) 48.47
Overall Average MPG (Screen) 49.14

Winter Average MPG (calculated) 47.10
Winter Average MPG (Screen) 47.80

Best Tank (calculated) 65.63
Best Tank (Screen) 57.60

Most Recent MPG (calc) 43.47
Most Recent MPG (Screen) 44.00

Summer Average MPG (calculated) 50.76
Summer Average MPG (Screen) 51.38

Worst Tank (calculated) 31.88
Worst tank (Screen) 41.40

Average MPG Actual

Average MPG Screen

Calculated vs. Screen

Percent Difference

Note, this is for all types of driving in all seasons. Also for those who may not know, the Prius currently has a fuel tank bladder (for emissions control) that makes the tank size vary from fill up to fill up. That is why I am tracking both the standard miles travelled since last fill up, divided by fill up gallons as you would do to calculate your own MPG. And I am tracking the Prius’ own on screen prediction for each fill up. I also compare the differences, and as you see over time the difference between methods is not very much. How does the Prius figure its own MPG? As I recall, it monitors the fuel flow at one fuel injector, using that to calculate the total fuel consumed, and then divides by miles traveled. The result of the comparison is that individual tanks vary greatly depending on the temperature of the bladder. But, over time this will even out. You also see differences by winter or summer driving. For my purposes, I am calling the warmer months summer, and the colder ones winter. This is for the sake of simplicity. Also, for the statistically minded people, I am using a weighted average to calculate the overall average from the Prius interior display of MPG. It should also be noted that the Prius, along with all other cars, recently underwent a change in how the estimated MPG for the window sticker of a new car is calculated. When I bought mine, the estimated MPG was as listed under “Old MPG estimates”. At the time, my overall MPG was just at 50 MPG, missing the EPA figures somewhat. Now, with the new predictions as listed, I would make that combined MPG with room to spare, even if my current overall listing is dropping to 49.14 as stated above. Why is my MPG dropping? I have different tires now than when I started, and evidently the MPG is a bit lower than the standard issue. Also, I am making shorter trips now than initially. More on that later. . .

Old MPG estimates
60 City
51 Highway
55 Combined

New MPG estimates
48 City
45 Highway
46 Combined

Thursday, March 19, 2009

After the solar panels were moved...

The move of the 20 solar panel array went fairly smooth. Actually, as far as jobs like this usually go for us, it was flawless except for one brief glitch. When the switch was turned back on, there was an error message on the inverter, and no power flowing. It was late afternoon. Maybe there should have been a bit of power by then, but we waited to see what it would do the next morning. You guessed it; no juice then either.

The installer came back, and after re-tracing it all, he discovered he had wired the individual panel assemblies in parallel instead of series. So we were only seeing the voltage of one group. Once he fixed that, we were back online with only 2 full days of production missed.

You should be prepared if you do anything with alternative energy to become a nitpicker when it comes to counting your production, mileage or electric bills. That couple of days can make a difference if you are off for some reason. For us, it did not matter that much since this is a time it is normally not that sunny anyway, and that we are not yet on the maximum high use charges.

So far, it looks good. We are already surpassing our normal daily production just by having the panels pointed more towards the sun in the afternoon. One glitch in the overall plan was that at the same time we were moving the panels, we were having a small pond put in. That pond has a small waterfall. That requires a pump. You see where I am going here. This is what normally would be considered a waste of electricity. And we have already cut back the run time from 24 hours a day to just 12. For the first month it had been on, it cost us an additional 12 kilowatt hours a day. Part of our reason to get the solar panels was to be able to afford to run our AC in the summer. This pond would tend to cut into our extra capacity, and I think it might lose out in the long run if it goes up against our comfort.

Wednesday, March 18, 2009

My Green Energy- from Hybrid Prius to Solar Panels and Tankless Water Heaters

I was in a volunteer in High School for a group called “Recycle for Survival.” That was around the time of the first Earth Day, to let you know the time frame of my earlier environmental education. I have been interested in photo-voltaic energy technology since I heard about it when I was in college, way before anyone was using it on a wide scale. Even today, it is still in its real infancy as far as total production goes. In 2001, I purchased my first Toyota Prius, which actually was the first one sold in my town. In 2004, my second. Did I tell you I was an early adopter? In 2007 we installed a 2.2 Kilowatt photo voltaic array on our roof. A few years later, we purchased a tankless water heater. Here is a bit about all that. . . Throughout my Prius ownership, I have tracked my MPG results on a spreadsheet I created, which is just under 50 MPG for all seasons, and all driving types. I added a section to that later to track our household energy use for the solar array in particular. For our solar array, our bill is calculated on an annual basis. That is running less than $100.00 a year, including the $60.00 or so of fees everyone pays no matter what they do to try to save. Since adding our tankless water heater, our summer natural gas bills are usually under $5.00 a month. It really does not pay to heat up a tank of water all day when no one is using it. And it does seem to pay to only heat up the water you use, and stop when you turn off the tap.

My main goal in the beginning is to talk a bit about the solar cells, since that is the biggest investment, and probably the biggest commitment of what we have done. Like I said, we have a system that is around 2.2 Kilowatts and is grid tied. That amounts to 20 panels. That same system today would require fewer panels because of efficiency increases in the panels. The cost of this system installed was around $20,000. At the time, there was a program in place that provided us a rebate of around $8,000. It was still pricey. If we had acted six months sooner, our rebate would have been closer to $10,000. If you are considering doing this, and you are in an area that has rebates, putting it off could cost you.

Installed and in use, our system only achieves 1.8 Kilowatts. This is simple internal losses in the panels, and inverter. Your contractor can advise you on your needs, and how many panels you need to get to lessen the impact of the internal losses, and still make sense for your energy needs. You want to get as close to your energy needs as possible without over production. At least for us, if we have a surplus at the end of our annual billing period, PG and E errases it.

Our system came out pretty close. Your contractor will want to see a year’s worth of electric bills to calculate the size of your system. Your electric company may also need to see this if you opt, as we did, to change your meter and rate schedules. Part of why we are only $100.00 a year, is because we applied to change our metering to what is called “TIME-OF-USE” metering. At the same time we did that, we switched to an E7 rate schedule. Normally, in California, residential use is metered at around 18 cents a kilowatt hour. The E7 rate is split in a way that charges you a higher rate in the higher demand hours, and switches to a lower rate to the rest of the day. This lower rate also applies to holidays, and weekends. For us, from May through October, from noon to six, we would pay 32 cents a kilowatt hour, and the rest of the day it would be 9 cents. Where this is important for grid tied systems, is that your heavy production hours are from noon to six. This means that the surplus production during those hours is sent back to the grid showing as a credit on your meter. Of course, you can use anything in your home as this is happening. But, you have to remember that anything you use means less of a surplus. This system would be best for those when either are not home on weekday afternoons, or who are home but do not use much in the way of electricity. It is not so bad really. If you are home, do things before noon, or after six.

As I am typing this, our system is off-line and being moved. Planned construction on the house meant that eight of our panels would be in the way of our new roof. And, as luck has it, our inverter does not allow the system to run in a split configuration unless both of the sets of panels face the same direction. Since we do not have money for a new inverter, we had to change the panels from their original southeast direction to a section of roof that faces southwest. This may eventually work out in our favor. Due south would be the best direction to have the panels, but you can only deal with the way your house or your roof faces, unless you want to add more money to the installation for mounting to the south, or even more money for systems that track the sun. Sometimes you just work with what you have. As I said, it will work out for us. This is because of that E7 rate schedule we have. Moving the panels to the south west will put them towards a place they will get longer afternoon hours of exposure. Since our rates are higher in the afternoon than they are in the morning, this should get us more of a surplus at the higher rates. Maybe with this our next bill will be completely zeroed out. I am looking forward to it.