Solar Power Blog from SunCal Solar, Inc.

California Net Metering Cap Doubled

blog@suncalsolar.com (Robert at SunCalSolar.com) — Mon, 08 Mar 2010 13:38:00 GMT

California Assembly Bill 510
California Assembly Bill 510 was passed on February 18th. This bill doubles the cap on net metering in the state (see previous articles What Does Net Metering Mean and What is Net Metering).

This new law changes the maximum cap from 2.5% to 5% of the utilities' peak demand. This could be a very big deal in the future. What it means is that before this change the utilities only needed to agree to "net meter" up to 2.5% of their peak demand. So once this was reached homeowners would no longer have the availability of net metering for their solar electric system. However, this maximum has been doubled which means many more homeowners for a longer period of time will be able to setup net metering with the utilities to take advantage of Solar Electricity.

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Robert Morse
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SunCal Solar, Incorporated
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Smart Metering Update - Smart Meters

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 05 Mar 2010 14:26:00 GMT

SDG&E Smart Meter Program Information from SDG&E Email

How a smart meter installation works

SDG&E notifies customers by mail a few weeks before the smart meter installation takes place. Read more »

Save Energy and Save Money

The energy use collected by smart meters will help customers understand energy use habits and the best ways to save. Read more »

What happens to SDG&E’s meter readers?

For quality assurance purposes, after initial installation, meter readers will continue to read meters for the next few months. Eventually, meters will be read remotely. Training and workshops will be offered to SDG&E’s meter readers to help them transfer to other jobs within the company.

For more information about the Smart Meter Program, visit sdge.com/smartmeter or call 1-800-411-7343.

Thank you for your interest in SDG&E’s Smart Meter Program.

SDG&E’s smart meter initiative is part of California’s Energy Action Plan, a statewide roadmap for achieving a reliable, affordable and sustainable energy future.

Smart meter installations are well underway
SDG&E® officially began the areawide roll-out of its new smart meters in March 2009. We’re currently replacing 1.4 million electric meters and upgrading 900,000 natural gas meters. Through Feb. 2010, we’ve installed about 500,000 meters in San Diego County and will be finished replacing or upgrading the meters by year end. We’ll wrap up the smart meter installations in south Orange County in 2011. By that time, all SDG&E meters will have the new smart technology.

In order to accomplish this monumental installation task, SDG&E’s technology provider has engaged the services of VSI Meter Services. VSI is an experienced meter service contractor whose expertise is meter installations.
Learn more about VSI.

Smart meter capabilities
A smart meter system allows for two-way communication between a customer and SDG&E. The smart meters record energy use information daily. The technology allows for the meters to be read automatically without the need for a physical visit from one of SDG&E’s meter readers. However for quality assurance purposes, after meters are installed, meter readers will continue to read meters for the next few months. In addition, customers will still need to allow SDG&E access to the meters for maintenance and safety checks.

The two-way communication capability means SDG&E will be able to better manage overall energy needs, implement “green” demand-response programs, quickly detect power outages as they happen, and offer enhanced customer services.

SDG&E HOME PAGE | RESIDENTIAL CUSTOMERS | ONLINE BILL PAY | REBATE PROGRAMS

Electric Utilities Will be Forced to Buy Your Extra Solar Electricity

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 18 Dec 2009 13:59:00 GMT

Utility Company Pays You for Solar Electricity
In California a new law called AB920 was passed not long ago that will force your electric company to buy any solar electricity that you don't use (BLOG about AB920). This law has to go into effect sometime before Jan 1, 2011 which means it will go into effect sometime in 2010.

Remember, this does not change net metering (see also BLOG on net metering). In the past if your solar electric system generated more electricity than you used, then the utility company got that electricity for free. In other words you paid for the solar electric system and the extra was free to the utility company. Of course that should never happen on a properly sized system (for more information see also Sizing a Solar Electric System). But with this new law the utility will have to pay you for any excess electricity you don't use.

But Wait
Now, before you go out an install that enormous, gigantic, humongous solar photovoltaic system there are many unknowns. But the BIG unknown in my mind is what price will they pay? Nobody knows. That is all being worked out.

What Will They Pay for Your Solar Electricity?
However, it seems very unlikely that they will pay the higher rates in Tier 3 or 4 rates (see also Tiered Electric Rates). In fact it's not even clear that they will pay the Tier 1 or 2 rates. These tiered rates are all full retail rates. They may only pay a wholesale price or utility cost price. Nobody knows! So in the end this may not be that big of a deal.

Plan Carefully and Make Informed Choices
As always it seems best to plan carefully and size your solar system properly for your needs.

Solar Energy and Your Electric Bill

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 04 Dec 2009 14:56:00 GMT

Electricity Consumption
All the electric appliances in your home use power. Your lights, refrigerator, microwave, television, stereos, air conditioner, heater (even if it's gas heating because the blower fan uses electricity), electric stove/range, jacuzzi, pool pump, and electric pool heaters all consume electricity. You are then billed by the electric company for the amount of electric energy that you use. This energy is measured in kWh (which stands for kilowatt-hours).

What does a "kWh" mean? 1 kWh is 1,000 watts used for 1 hour. Or you could think of it as the same as turning on twenty, 50 Watt light bulbs for one hour (20 bulbs x 50 Watts x 1 hour = 1,000 W = 1 kWh).

You can also see the kWh's that you are being billed for on your electric bill (see also Deciphering Your Electric Bill and Tiered Electric Rates).

Solar Power Production
Any power you produce from solar electricity is simply subtracted off your bill. For more details, see articles on Solar Power 101 and System Sizing. The energy your solar electric system produces is also typically measured in kWh's.

Solar Energy Production and Electricity Consumption
Solar electric systems produce energy while your home's appliances and lights consume it.

You can think of power used/consumed as adding on to your electric bill while power produced by solar is subtracted from your electric bill. In other words, energy that you are billed for by your electric company in kWh = Total Energy Used minus Total Solar Energy made by system.

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Robert Morse
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SunCal Solar, Incorporated
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What are kWh or Kilowatt-Hours?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 27 Nov 2009 14:06:00 GMT

kWh or KiloWatt-Hours

If you leave a 60 Watt light bulb on for one hour then this uses 60 Wh (or Watt-Hours) of energy. Most solar electric systems are considerably larger and so are measured in Kilowatts (1,000 Watts) and Kilowatt-Hours (1,000 Watt-Hours or kWh).

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Robert Morse
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SunCal Solar, Incorporated
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What is the Difference Between Kilowatts DC (kWDC) and Kilowatts AC (kWAC) for Solar Electricity?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 20 Nov 2009 14:56:00 GMT

Solar Electricity: Kilowatts DC (kWDC) and Kilowatts AC (kWAC)
If you have been investigating solar you have probably already heard the terms kWDC and kWAC. But the differences between these two are often explained very poorly or not at all.

kWDC or Kilowatts DC are the direct current (DC) power produced by the solar electric panels prior to any conversion to household electricity (see also inverters).

KWAC or Kilowatts AC is the alternating current (AC) power that is used by your home. This is electricity that has been converted ("inverted) from the DC produced by the panels to the AC used by your home and provided by the electric company (see also Solar Electricity Basics).

What are Watts and Kilowatts?
Watts and Kilowatts are a measurement of instantaneous power (1 kilowatt = 1,000 Watts). To help put this in perspective: You are probably familiar with a 60Watt light bulb. A 60 Watt light bulb consumes 60 Watts of power when it is on. Also "kilowatt" or 1,000 Watts is often abbreviated as"kW".

Electrical Energy Losses
Between the DC from the panels and the AC used in the home there are losses caused by multiple factors. These losses come from things like the conversion to AC (inverter), wire losses, dirty panels, shading, and other imperfections in the system. It is not possible to get this to 0% loss. There will always be some loss going from DC Solar Panels to AC Electricity Used. So there is a conversion factor that says some percentage of the power from the panels will be available to your home (or electrical grid - see also Solar Electricity Basics). Often this conversion factor comes out to be between 70% to 85%.

How Losses Affect Your Electrical Generation
What this means to you is that if your solar panels produce 1kW of power then you will likely get 0.70 to 0.85kW of power to use in your home. If someone says they can get you a 95% conversion rate, then they are not including everything, lying, or just don't understand how to properly calculate the conversion losses. I would avoid doing business with this person. Anything over an 85% conversion is pretty unlikely.

kWDC vs kWAC Explained
Now kWDC is the power produced by the solar electric panels; and kWAC is the usable power to your home after the losses described above.

Using the same example as above: What this means is if your solar panels produce 1kW of power this is 1 "kWDC". And since your conversion factor for losses are likely to be in the range of 70% to 85% then you will get 0.70 to 0.85 "kWAC" of power to use in your home.

The actual conversion factor will be determined by many design details like the specifications of the inverter, wire diameter and length, operating temperatures, and many other details. This is where choosing a good design and installer is crucial.

Comparing Competing Bids for Solar Electric Systems - kWDC vs kWAC
You should be careful when comparing kW numbers. First be sure to compare kWDC to kWDC. And kWAC to kWAC. Never compare kWDC to kWAC numbers because that's like comparing "apples to oranges". Also, it's probably best to look at both the DC and AC numbers when making comparisons between competing systems or bids.

kWDC Comparisons
The kWDC is a rating on the solar panels based on standardized test conditions. This is a pretty good comparison to make between different systems. Especially, when comparing prices on competing bids. And when you consider that the solar panels are typically the most expensive part of the entire system.

kWAC Comparisons
The kWAC is what you will be actually using or deducting off your electric bill (see Solar Electricity Basics) so this is what you are probably most interested in.

HOWEVER, remember that the conversion factor for losses is an ESTIMATE only. The only way to know what this will actually be is to install a system and take measurements over time.

Conclusions
I would recommend looking at both the kWDC and kWAC when comparing competing systems. Make sure the conversion factor looks reasonable (probably in the 70% to 85% range). There are some unscrupulous individuals that will try to mislead you on comparing kWDC and kWAC or unreasonably inflate the conversion factor. Be informed, keep reading, and compare both the kWDC and kWAC numbers.

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Robert Morse
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SunCal Solar, Incorporated
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NC Times - Region: County Explores Solar Loan Program

blog@suncalsolar.com (Robert at SunCalSolar.com) — Tue, 10 Nov 2009 14:53:00 GMT

Article from North County Times about "micro-bond" (AB811) financing for solar systems takes one more step to allow homeowners to pay for solar systems in their tax bill in Riverside County. San Diego County has been pursuing a similar plan for some time now. However, the biggest obstacle seems to be getting the money for the loans for the microbonds.

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REGION: County explores solar loan program.

Initiative could remove cost obstacle to rooftop panels

By DAVE DOWNEY - Posted: Friday, November 6, 2009 10:35 pm

Many people would love to put solar panels on the roofs of their homes and take the edge off those crazy summer air conditioning bills, if only they could afford the up-front installation cost often of thousands of dollars.

Soon, however, Riverside County residents may not have to foot that expense.

In late September, the Riverside County Board of Supervisors voted unanimously to study creating a program by which the county would provide loans to homeowners to install panels that generate electricity from the sun for use in their homes.

The county also may issue loans for home improvements that save energy and water.

At the suggestion of Supervisor John Tavaglione, the board asked its staff to explore the idea of setting up a solar loan program for the entire county, including its 26 cities.

Palm Desert already has a loan program, and Murrieta planners are looking into the idea.

Tavaglione, in a telephone interview recently, stressed that a county wide program wouldn't pre-empt any individual community from going it alone, as a recent state law authorizes both counties and cities to issue such loans. He said he just thought it would make sense for the county to administer a regional program on cities' behalf because loans are repaid over 20 years through assessments on twice-a-year property tax payments. And the county's treasurer-tax collector sends out those bills.

County spokesman Ray Smith said officials will be surveying cities to gauge their interest in a regional program.

Regardless of the scope of the county's initiative, Tavaglione said it could put a lot of people into position to install solar panels who couldn't otherwise afford them and help them save hundreds of dollars on electric bills.

"Everybody today is looking at saving their hard-earned cash,"Tavaglione said. "And this is just another way to become moreefficient."

Tavaglione said the county will check to see whether it can obtain funding for loans through the federal stimulus program, a finance corporation set up by California State Association of Counties or the private sector.

"We need to look at all options," he said.

The concept of a public loan to finance rooftop solar projects and energy- and water-efficiency upgrades is something that grew out of Assembly Bill 811 by former Assemblyman Lloyd Levine, D-Los Angeles, which was signed into law in 2008. The legislation authorized city and county loans for renewable energy and energy-efficiency projects.

Assembly Bill 474, by Assemblyman Bob Blumenfield, D-San Fernando Valley, was signed into law last month by Gov. Arnold Schwarzenegger and extends such loans to water efficiency upgrades.

The bills are a product of the state's move to curb emissions of carbon dioxide and other greenhouse gases linked to climate change.State officials have said that almost every home in the state will have to become more efficient, or obtain its electricity from green sources such as sun and wind, for California to make a serious attempt to slash emissions by a mandated 30 percent by 2020.

Many people would love to contribute to that effort and cut their utility bills in the process. But most cannot afford the expense, said Cisco DeVries, president for the Oakland firm Renewable Funding, which financed Berkeley's pioneer loan program.

"The piece that has been missing all this time is how to pay for it," DeVries said.

And he suggests the loan program is that missing piece.

Even with federal tax credits and state rebates, solar panels can cost homeowners anywhere from $25,000 to $60,000.

Wildomar retirees Richard and Sylvia Stephens, for instance,said they spent $60,000 on a ground-mounted network of solar panels they installed a year ago this month.

Sylvia Stephens said that, while the couple were able to come up with the money, they know others who simply can't.

"This would help people because of the high expense of putting it in," she said.

However, cities and counties can't help homeowners foot the expense unless they can come up with financing for making loans.

"Good luck. It's going to be tough," said John Weil, chief of staff for San Diego County Supervisor Pam Slater-Price, when told of Riverside County's initiative.

At Slater-Price's urging, the San Diego County Board of Supervisors explored a similar countywide program at the beginning of this year. The county recently had to abandon in its initial plan to obtain financing through banks.

"What we found was, banks were willing to finance, but only at their usual rates," Weil said. "And we didn't think that would be a bargain for homeowners."

Last month, the board changed direction and sought funding instead from the San Diego-based California Center for Sustainable Energy.

"Under this route, only unincorporated area residents may apply or financing," Weil said. "The cities would need to take their own action to join with CCSE. However, it could be that, if that happens, we could create one large umbrella program."

Fifteen states have passed laws authorizing renewable-energy loan programs, but there are only two umbrella programs like the one Riverside County would like to create, DeVries said.

DeVries, who is tracking the green loan trend, said both are working well. He said California's Sonoma County has issued $22million in loans to date, and Boulder County, Colo., has loaned $10million.

Just two other California counties ---- Orange and San Francisco---- are close to launching programs, he said.

Still, DeVries said enthusiasm is building despite the financial obstacles. One day, he figures, such programs will be widespread and houses with solar panels will fill every block.

"Thirty years ago, nobody had curbside recycling and only 1 or 2percent of people did it," he said. "And now in this state it's law. Every city must provide curbside recycling and we're diverting half of our waste stream. Ten years from now, we may divert half o four energy use."

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Article Source: http://www.nctimes.com//news/local/swcounty/article_1b2a1e06-ba64-56ee-b1f1-4afdaba1aa6e.html

Installing Both Solar Electric & Solar Hot Water?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 06 Nov 2009 14:09:00 GMT

Installing Solar Electric & Solar Hot Water at Same Location

So you want to get as much benefit from the sun as possible and you would like to install both solar electric and solar water heating. There are some things to consider when you do this. (see article on Solar Electric vs. Solar Water Heating?)

Solar electricity is more sensitive to shade than solar hot water so put the solar electric panels where there is the least shade. And put the solar hot water in the next best location.

Plan for both Solar Electric and Solar Hot Water at the same time so you avoid:
(1) creating extra work and costs by needing to relocate solar water panels or
(2) significantly reducing your solar electric energy harvest by putting the panels in a place that gets shaded at part of the day or year. (see article The Location of the Sun is Crucial for Every Solar Electric System)

You don't have to install them both at the same time, just plan for them at the same time. If money is a concern then install the one that will benefit you the most (Solar Electric vs. Solar Water Heating?)

I have seen systems that integrate solar electric and solar hot water into one panel, but these concern me. It's like if you own an-all-in-one stereo that has a CD player, DVD player, turntable, etc all built into one unit. When one part breaks you often have to replace the whole thing not just the broken part. Additionally, combining electricity and water into the same panel seems to be asking for problems. Solar hot water has its own set of constraints and concerns and solar electric has its own different set.

When you want to install both solar electric and solar hot water, careful planning is the key to success.

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Robert Morse
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SunCal Solar, Incorporated
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SD Union Tribune: County wins big share of solar funds - Projects could up regional capacity by 40 percent

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 30 Oct 2009 19:09:00 GMT

From San Diego Union Tribune on October 30, 2009

Full Story: County wins big share of solar funds - Projects could up regional capacity by 40 percent

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Robert Morse
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SunCal Solar, Incorporated
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PV Tech: PV cost study shows no better time than now to go solar in the US

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 23 Oct 2009 14:30:02 GMT

Source: PV Tech - October 22, 2009 - PV cost study shows no better time than now to go solar in the US

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SunCal Solar, Incorporated
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How Do You Know Your Solar Electric System Working?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 23 Oct 2009 13:19:00 GMT

A well designed and properly installed solar electric system requires very little maintenance. But it's still a good idea to watch your system for problems if they should ever occur.

System Monitoring: Is your solar electric system working properly?
Solar electric system monitoring is an often overlooked part of a well designed system. You probably would like to know if a solar panel or inverter ever fails. And I bet you would prefer to know this before your electric bill goes up at the end of the month. If something ever fails, you might just think your usage is higher for the month and not consider that your system may not be working properly. And so you could wait another month "just to see". This costs you money in your electric bill.

If instead you have a monitoring system installed then you can check anytime you want to see if everything in your solar system is working properly. Monitoring with string inverters can do a good job of monitoring each string of solar panels; However, microinverters go one step better and offer great per module and per inverter monitoring, so it's easy to pinpoint any problems right away (be sure to see the earlier entries on Microinverters and Monitoring and More Power from Microinverters).

If your system is older and you have not been paying much attention to it, then it may be worth having a solar electricity professional take a look at it to make sure everything is in order.

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SunCal Solar, Incorporated
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CSI Solar Electric Rebates Drop Again in SDG&E Territory - 29% Decrease

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 16 Oct 2009 13:58:00 GMT

Decrease in California Solar Rebates
The California State Rebate for residential solar electric systems in the SDG&E territory dropped from $1.55/watt to $1.10/ watt. Or about a 29% drop in residential cash rebates. These rebates will continue to drop over time until they go away completely.

What Does this Mean?
If you were to install a mid-sized 5kW solar system then the cash rebate you would receive has dropped from $7,750 to $5,500. A decrease of $2,000. For a larger 10kW system the rebate decrease would be $4,000.

Planned Rebates Decreases
This is exactly as planned. It is NOT because of state financial problems. It is simply the natural progression of the state rebate program. As the amount of installed megawatts (MW or millions of watts) of solar electric power increases, the state rebate is set to decrease in predetermined steps. This will continue until the rebates go to $0.

This current decrease is the planned decrease going from the state defined "Step 5" to "Step 6". These steps were defined years ago when the rebates were set up. You can find more information on these steps at the state's "Trigger Tracker" website.

The Good News
The good news is that prices on many solar panels have dropped; Making solar more affordable than ever.

New Laws will Force California Utilities to Buy Excess Electricity - Will It Matter?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Tue, 13 Oct 2009 16:52:00 GMT

New laws will force California electric utilities to purchase excess power produced by homes and businesses with solar electric systems with net metering.

But will it really make any difference? Pricing and details of how program will be implemented have not been set yet. Pricing and implementation details can make this a great program or make it completely useless.

Only time will tell . . .

From Renewable Energy World

Source Article: http://www.renewableenergyworld.com/rea/news/article/2009/10/feed-in-tariff-and-met-metering-bills-signed-in-california

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Robert Morse
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SunCal Solar, Incorporated
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Why Does Solar Electricity Have Such Low Maintenance?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 09 Oct 2009 14:23:00 GMT

Solar electric systems are expected to last 20 to 40 years depending on who you ask. Even at the low end of that range that's a long time. Think of all the changes in your life from where you were 20 years ago.

No Moving Parts
Almost all modern solar electric installations have no moving parts (except for shutoff switches and circuit breakers). So there are no mechanical parts to wear out or to be lubricated. A few inverters have fans but these are quickly disappearing.

No Fluids to "Top Off" or Replace
There are no oils or coolants to fill up or replace. There are no pumps and no pipes to corrode.

What Maintenance is Required for Solar?
A properly installed system should require very little maintenance. The primary maintenance that solar electric systems need is to keep the panels free of dust, leaves, bird droppings, etc. Also, inverters could fail and need to be replaced in the future. However, most inverters have 10 or 15 year warranties. I take that as a good indicator that the manufacturer expects them to last at least that long.

Silent Operation of Solar Electric System
Your solar electricity generating system will operate almost silently, except for the low hum of your inverter(s). You can hear them if you listen closely.

To know more about how your system is running, you will need to use a meter of some sort. Your utility meter is a good indicator of whether your system is working or not. Midday during a bright sunny day your utility meter should run backwards when not much electricity is being used in the house (see also Make Your Electric Meter Run Backwards, Legally). To get more detailed system information you will need a monitoring system (see also Another Major Advantage for Microinverters).

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SunCal Solar, Incorporated
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Solar Electric vs. Solar Water Heating?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 02 Oct 2009 14:42:00 GMT

What's the Difference?
Solar electric systems are completely different from solar water heating systems in almost every way. The only thing they have in common is that they both collect energy from the sun.

Solar Electricity Systems
Solar electricity starts at the Solar Panels (see also Solar Panels). These panels are often located on the roof and are full of solar cells that convert the Sun's energy directly to electricity (see also How Solar Works). They use "semiconductors" and "quantum physics" to absorb light and release electrons that become an electric current.

But you don't need to know all the details of that. Just like you don't need to know how your engine runs to be able to drive a car. You just need to know how to use it. And you already know how to use your electrical appliances and lights in your home.

What is important is that the electric current created by a solar electric system can be used to power your home. Fortunately, the solar electric system is automated. It turns itself on when the sun comes up and turns itself off when the sun goes down. It converts the electricity to the same type that your home uses (see also Type of Electricity). It knows to automatically use the power made from your solar panels when the sun is up and to use the utility company's electricity when the sun is down (see also article on Net Metering). There is not much for the owner to do. It would be difficult to make it much easier to run a solar electricity system.

Solar Water Heating Systems
Solar water heating is a even simpler. At least, no quantum physics are needed. A liquid fills a collector that sits on the roof or some other exposed area. This liquid then is circulated to heat your water (in some cases the water to be heated is itself circulated, like is often done for pool heating).

This solar heated water can be used to heat your pool or your home's hot water. For home hot water heating (for showers, dish washing, etc.) water can be used to "preheat" water before it goes into your regular water heater. This is to reduce your water heating bill. Also, home solar water heaters usually require an extra tank to store the heated water in addition to your regular water heater. So you need the space for this tank.

With solar water heating you have to be very careful that there are relief valves, drainage valves, and antifreeze protection to protect the system from freezing and overheating which can destroy the collectors.

How to Choose: Solar Electric or Solar Water Heating
Look at your gas and electric bill. How much of it is for electricity and how much of it is for gas? If you are like most people your gas bill is a small part of the total bill and your electric bill is much larger. So where would you prefer to save money? On the relatively small gas bill or the more substantial electric bill? I'll bet the electric bill gets your attention. If this is the case then solar electricity could be the right choice.

Solar electric systems typically cost quite a bit more than solar water heating systems, but they also typically save a lot more money on your bills and pay for themselves very quickly (see also Solar Electricity as an Investment and System Sizing).

Imagine getting rid of 50%, 80%, 90% of your electric bill with solar electricity. Would that be valuable to you?

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

Another Major Advantage for Microinverters

blog@suncalsolar.com (Robert at SunCalSolar.com) — Sat, 26 Sep 2009 15:41:00 GMT

Solar electric systems have no (or few) moving parts and operate almost silently (slight hum from inverters) so it's not that easy to see if your system is workingproperly.

Microinverters Give You More Information
Microinverters have a great advantage when it comes to monitoring. With microinverters, a system can easily be setup that allows you to see power production over time (today, last week, or since the system was first installed). It can show you things like voltage, current, power, temperature and how it changes through the hours of the day or the months of the year. All of this can be shown in an easy to read graphical interface so you can quickly scan it to see your system working properly. This is valuable information to let you know your system is working properly.

Instant Notification
Additionally, the system can be setup to send an email to you and your installer if a module or inverter fails. This means you can have the problem fixed right away and not wait until you notice your utility bill has increased.

This should increase your system "up time" and produce more electricity, which is the main goal of a solar electric system.

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

A Simple Way to Get More Electricity from Your Solar Panels - Microinverters

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 25 Sep 2009 14:24:00 GMT

More Electricity from the Same Solar Panels?

Micro inverters are small boxes that go underneath each solar panel. They optimize the energy production and convert the electricity to what your home uses right at the panel. They have some significant advantages! They can often produce more electricity from the same panels.

Two Main Types of Solar Inverters - String and Micro
As I've discussed in previous postings the inverter (see also Key Components of A Solar Photovoltaic (PV) System: The Inverter) is what converts the electricity into power that your home uses and is compatible with the utility company's "grid power" (for more info click here: grid power or electricity AC and DC.

There are two main types of inverters: large string inverters and microinverters. This may be a bit of an oversimplification but it's sufficient for this discussion. String inverters for the home are typically a large metal box that hangs on a wall in the garage or on an outside wall. They are fairly heavy at about 50 to 100 lbs. Typically they are are a couple of feet wide by a few feet tall and less than a foot deep. They take up space.

Microinverters are small boxes that are installed under each solar panel. They are measured in inches and don't take up any garage or wall space.

Microinverter - Optimize Power at Each Solar Panel
With microinverters, the output of each solar panel is optimized at each panel so if there are any less than perfect conditions on any one panel it simply lowers the output on that panel instead of the entire string like a string inverter. String inverters optimize for an entire string of panels so a problem with one panel can pull down all the other panels in the string. While using microinverters typically results in more energy being delivered from your panels.

You might ask what are "less than optimal conditions". Dust and bird droppings on panels can ask just like the shade from a tree or chimney and significantly reduce electricity production. With microinverters problems like these effect only one panel, but with string inverters this affects an entire string of panels.

Microinverter - No Single Point of Failure
In the unlikely event that one microinverter fails you simply lose power from one panel. However, if a large string inverter fails then EVERY panel connected to that inverter stops producing power for you. If you have one inverter this means your entire system is down. This is not true with microinverters. If a micro inverter fails, all the other panels should continue to produce electricity for your home. All of this means higher reliability and more "up time" that your system is producing power for you.

Microinverter - More Electricity - Lower Electric Bills

Using microinverters should better optimize the amount of electricity generated and they should have more "system up time". Both of these mean they should produce more electricity for your home than a string inverter. This results in lower electric bills!

There are other "techie" reasons to use microinverters to get the most out of your electrical system, but they are beyond the scope of this article and most of the major points are already covered here.

The only drawback I can think of with microinverters is they are not as easily accessible as a string inverter so if maintenance is needed it is a little more complicated because they are under a solar panel. However, this should not be a big issue with a properly designed and installed system.

Otherwise, it seems that microinverters are the way of the future because of their many advantages.

Contact Us with Your Questions at: blog@SunCalSolar.com

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

Questions on Solar Electricity?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Thu, 24 Sep 2009 13:33:00 GMT

Do you have any unanswered questions about Solar Electricity? What would you like to see answered in this BLOG?

Is there anything about solar electricity that just doesn't make sense to you? Or concerns you? Tell us what you like, don't like, or just don't understand.

There is a great deal of misinformation and myths about solar power. This BLOG intends to replace those with accurate information for you.

Contact Us with Your Questions at: blog@SunCalSolar.com

Or Ask a Question by Clicking Here: Submit Question for Blog

Do You Like This Blog? Tell Your Friends About It: www.SunCalSolar.org.
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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

If I Install Solar Power Today on My Home, Won't It Be Obsolete Next Month, Next Year, Next Decade, ... ?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 18 Sep 2009 14:18:00 GMT

Waiting to Install Solar Electricity (Power)
I hear this question from time to time and I have a standard answer. Yes, it will become obsolete. HOWEVER, you could say the same thing about buying a personal computer (PC); If I buy a computer today, there will be a newer, better, faster, cheaper version out in weeks or months from now. Right? Yes, that's all true. But if you waited to buy a computer until the final, "ultimate" PC arrived you still would not own a computer. And worse than that you would have lost all the benefits of using a computer in the time you were waiting. Imagine not having a PC.

Waiting Just Doesn't Make Sense
How long would you wait for the "ultimate" in solar technology to arrive? 5 years, 10 years, 20 years. I think you'll be waiting a long time. Solar power technology is continuously getting better just like your personal computer.

Now think about how much you will pay for electricity in that time you are waiting. And remember, almost everyone believes your electric rates will increase in that timeframe. Waiting will cost you in the electricity you are paying for. (see other articles: Take Control of Your Electric Bill, Protect Yourself from Future Rate Increases, and Make Your Electric Meter Run Backwards - Legally)

Rapid Changes in Technology
PC technology is rapidly evolving and so are solar electricity solutions. So it seems very likely that there will be a better solution in the future, but this is part of continuous change that will likely last for many years. Many of today's solar power solutions are excellent and will be even better in the future. To help make a decision just look at the costs of the system and the savings and think of it as an investment (see Solar Electricity as an Investment blog entry).

Note: However, PC's seems to be changing much more rapidly than solar electric systems. Maybe this is because the certification process for solar products involves many more bureaucracies like utility companies, their powerful lobbyists, local building permitting authorities, the CEC, and many others. However, this does have an upside; It makes solar electric systems very stable and safe.

The Benefits of Going Solar
So what if your solar electric system is not the latest and greatest in 5 years or 10 years from now. Your system should still be providing free electricity for many years after it is paid off. Remember these systems are expected to last 25 years or more. Most solar panels have a 25 year power guarantee warranty.

Of course you can always make the decision to upgrade to the latest and greatest solar tech at any time. But you will have benefited from all the free, clean electricity from the sun until that time.

To continue the analogy with computers: When your computer is a few months old or even a year old and a better models comes out. What do you do? Do you throw out the "old" one and rush out and buy a new one or do you continue to use that computer for a few years and enjoy all the benefits. Why would a solar electric system that is expected to last 25+ years be any different.

Free, Clean, Green Electricity
You have free sunlight falling on your house everyday. Maybe it's time to start collecting some of it to use for your own free, clean, green energy?

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

Going Solar - Environmental Whacko or Responsible Homeowner???

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 11 Sep 2009 14:49:00 GMT

Things Have Changed!
It was not that long ago that the stereotyped image of anyone installing solar systems was a long-haired, patchouli smelling, granola eating hippie type. But times have changed. Installing solar systems is becoming a mainstream part of our society. This is not just my opinion alone, but is shared with many others. CNN's Money magazine has a recent article about this subject (Press or Money). And there are many other articles and news about solar power these days. Just look at the paper or scan the Internet. Solar power even seems to be on our local, state, and federal governments' agendas.

What's Different for Solar Power Now?
Skyrocketing electricity rates coupled with tough economic times areforcing people to look at how to save money on their bills including their electric bill. Electric rates seem to keep going up and up with no end in sight. Do you know anyone that is predicting electric costs to drop? I don't.

Wouldn't it be nice if you could have the electric bill you used to have in 1990? How much has it gone up since then? How much do you think it will go up over the next 20 years? Double, Triple, Quadruple, or more? Solar power can be used as a hedge against rising electric prices.

Lower Prices for Solar Power
Also, solar power equipment is better than ever and at a lower cost than ever. The technology has become mainstream and mass produced. So the quality is great and the supply is there. Additionally, demand from other countries in the world has dropped off in the last year or so. This is primarily because of decreases in their rebates and incentives.

Remember the "supply and demand curve" from basic economics. This high supply in combination with lower worldwide demand has lowered prices and is driving a lot of installations here in the US. Prices are great and lots of people are taking advantage by adding solar power to their homes.

Rebates and Incentives
To make it even better, here in California we have cash rebates for installing solar. They commonly pay for about 20% of your total system cost. And the federal tax credit is 30% of the system cost. The government pays for almost half of the cost for a new solar electric system!

Solar Power: Lower Costs, Higher Quality, Government Pays Large Part
So installing solar can make a lot of financial sense. Especially when you consider how low your costs are right now and how high your electric bill savings can be.

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

Electric Cars and Solar Electricity

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 04 Sep 2009 14:24:00 GMT

Many Electric Cars Planned
There is a lot of talk about electric cars right now. Currently, we have only hybrid vehicles (i.e. gas with auxiliary electric power) readily available, but it looks like we will soon have plug in electric cars.

There are many new models planned to be sold over the next couple of years. Almost all the mainstream manufacturers are developing plug-in electric cars. In fact, it's amazing how much development work is being done right now. I'm convinced there will be some incredible cars available in the next few years.

Electric Motors
Electric motors have a wide power band (have power available from almost 0 RPM up to their maximum speed) and so don't need a heavy, complicated transmission that gasoline powered cars require. Electric motors are efficient and powerful. Some of the planned electric car models are very sporty. So don't think electric cars will be limited to the acceleration of a 1962 VW. Some models will be all out performance cars. You may not get the roar of a gas engine, but you can get loads of silent acceleration.

Batteries
Batteries are probably the in need of the most development work for electric cars to succeed. The good news is that many companies are pouring research and development on battery technology. So batteries will be rapidly improving over the next few years. They should be getting smaller, hold more energy, charge faster, and be more recyclable. It's all racing forward.

It's an exciting time!

Increasing Value of a Solar Electric System
When electric cars start to be sold a solar electric system becomes even more valuable. That electricity you capture from the sun can be used to charge your new car and keep your electric bills and gasoline bills low.

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

Make Your Electric Meter Run Backwards, Legally

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 28 Aug 2009 14:02:00 GMT

Did you know you can get your electric meter to run backwards? And it's completely legal. If you invest in a solar electric system (see also article Solar Electricity as an Investment?) you can start generating your own electricity. Anytime your "solar electric plant" is generating more electricity than you are using then your meter will run backwards, LEGALLY (see also article Solar Electricity Explained).

Electricity Metering Forwards and Backwards?
In the middle of the day when the sun is out and bright you should be producing your maximum electricity. Since many people are gone to work during the day not much electricity is being used. The amount of electricity you are making is likely to be more than you are using so the meter runs backwards. What happens to your bill in this case is that the larger amount that you are making is subtracted off of the smaller amount you are using. So when you take a larger value and subtract it from a smaller value you get a negative amount. This means you get a negative usage or a credit to your bill.

At night the sun is not out so your solar electric system is producing nothing and it is likely you and others are at home using electricity. Even though you are not producing any electricity you have the convenience of using the utility company's power. The amount you are making is 0 and so 0 is subtracted off your actual electric usage / consumption.

The credits generated in the daytime are effectively used up at nighttime (see also What is Net Metering with Respect to Solar Photovoltaic (PV) Power?). The utility company calls this Net Metering because the total amount of electricity you make in a year is subtracted off the total amount you use in a year. In other words the production and consumption of electricity is "Netted Out".

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

The Location of the Sun is Crucial for Every Solar Electric System

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 21 Aug 2009 14:50:00 GMT

How the sun hits your solar electric panels and any shadows created by the sun is arguably the most important design consideration for your solar electric system. This should always be carefully thought out during any design and before starting any installation.

Daily Sun Motion
The location of the sun is as it moves across the sky every day is crucial. You might be saying "of course" by now, but please read on. There's more.

Your solar electric system only produces significant power when it has direct sunlight is hitting it. As the sun comes up and runs its course across the sky, shadows form and move as the sun moves. If these shadows move across your solar panels they will significantly reduce the power output.

Seasonal Sun Motion
Equally important is how the Sun's location changes throughout the year. It changes quite a bit throughout the four seasons. Because of this, shadows can be very different in Summer as compared to Winter.

Shadows are typically longer in the winter and shorter in the summer. They may also shade different locations because their orientation can change. A shadow that does not shade your solar panels in the Summer could cause problems in the Winter. Again, if these shadows encroach on you solar system they can significantly reduce your energy production.

Seasonal Changes in Number of Sunny Hours Each Day
Summer days are longer (unless you're on the Equator) and so there are more hours of sunlight. In the winter,the days will be shorter and have fewer hours of usable sunlight. So noticeably more electricity is normally produced in the summer months.

How to Know If a Shading Problem Exists
If you have good trigonometry skills, you can use some math and charts that provide the Sun's path throughout the year for your approximate location. That's beyond the scope of this article.

A much easier way is to ask your solar design professional to provide a detailed shading analysis and determine if you have any shading problems. Sometimes it's very obvious and sometimes it will take detailed measurements to figure out the severity of problems.

Catch Shading Problems in the Design Phase
Every solar electric system design should include a thorough attempt to minimize any shading on your solar panels. And always remember how much shadows can change throughout the day and throughout the year.

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Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

Sunlight is the Key to Solar Power - The Obvious ... and Maybe The Less Obvious - 5 Points to Ponder

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 14 Aug 2009 14:24:00 GMT

Sunlight, of course, is the key to solar power; but what does that mean to you. For any solar electric system you want direct sunlight hitting your solar panels as much of the time as possible. The goal is to maximize the power that the system produces by maximizing direct sunlight. You want to avoid shading solar panels as the sun moves through the sky every day and throughout the year.

The Five Main Things to Keep in Mind to Get the Most Out of Your Solar Electric System Are:

Sunny Area Available to Install Solar Panels - First you must have a relatively large area to install solar panels. Typically, this is a large rectangular roof area that is free of shade throughout the year. This area could also be triangular ( /\ ) or other shapes with angles (like trapezoids).

If you have space on the ground you could also install a ground mounted system (see Installation Location Blog Entry).
Panels Southerly Facing - The solar panels should be facing generally South (at least here in the Northern Hemisphere) to improve power production of the panels. Southeast and Southwest are also usually good choices. East and West facing are ok. But avoid northerly directions, because you will get a poor energy harvest because northerly directions get less direct sunlight.
Daily Sun Path - Everyday the sun rises in the East, passes overhead, and sets in the West. Anything that will block sunlight as the sun crosses the sky can cause shading problems. Shading can be caused by trees, shrubbery, hills, nearby homes, chimneys, vents, etc. Shading will reduce the amount of power that is produced by the solar electric system. Avoid shading.
Annual Sun Path - The sun's daily path changes throughout the year. In the winter time it is generally more southerly and in the summer it rises more directly overhead. Also, the days are shorter in the winter and so produce less power. Remember, that the location of the sun at 10am in July will not be the same location of the sun at 10am in January. The sun is typically lower in the sky in the winter. This will change shading effects and can change the power produced. Avoid shading.
Angle That Sunlight Hits Solar Panels - The closer to perpendicular that sunlight hits the solar panel the better because it improves panel performance increases power output. Since the sun is moving from moment to moment and throughout the year this is not possible with a fixed mounting system. If you go though a lot of calculations you can find out that an angle of about 33 degrees from horizontal is best (and facing south). Tracking systems can be used to keep sunlight perpendicular to the panel, but these add considerable cost, weight, complexity, and maintenance. They also take up more space because they need space to move. Most roof mounted systems are not a good fit for a tracking system.

The Bottom Line is Simple in Theory, but a Bit More Complicated in Practice

Get the most direct sunlight on your solar panels that you can by locating them in a good location that maximizes direct sunlight and minimizes shading throughout the year. You probably have a good idea of areas like this from living in your home. When installing a solar electric system you should complete a thorough and detailed shading analysis that considers the location of the sun throughout the year and through everyday.

Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

Why You May Not Want to "Zero Out" Your Electric Bill With Solar Electricity

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 07 Aug 2009 14:31:00 GMT

Getting Rid of Your Electric Bill Completely May Not Make Financial Sense
Many people dream of getting rid of their electric bill completely. However, this may not be the best financial decision. The reason is simple, but not that obvious.

It all has to do with the tiered electric rate structure. (see also "System Sizing" BLOG entry). If you produce all of the power you need then you are producing power that you could purchase relatively cheaply in the Tier 1 and Tier 2 electric rates. It makes more financial sense to purchase the inexpensive Tier 1 & 2 electricity from the utility company and produce your own electricity for the relatively expensive Tier 3 and Tier 4 electric rates. This improves your payback period and rate of return. Use the electric company for their inexpensive electricity.

Having said this, it is possible that the Tier 1 & 2 rates could go up in the future. Or the cost of solar systems could drop so much that producing all of your electricity could make financial sense, but for now it does not.

There may be a good reason to produce all of your electricity that I have not mentioned, but it is not financial. It is to reduce carbon emissions and reliance on fossil fuels.

And just FYI, here in San Diego Gas & Electric Territory your minimum bill even if you produce more electricity than you use (or the same) is $5.17/month.

Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com

How Much Solar Power Do I Need?

blog@suncalsolar.com (Robert at SunCalSolar.com) — Fri, 31 Jul 2009 14:50:00 GMT

Install the Right Amount of Solar Electricity for YOU

Everyone's electricity usage is different. And so is everyone's goal for the size of their electric bill. In other entries I have mentioned there are reasons you may not want your electric bill to be "zeroed out". The main reason is that it may not be your most cost effective approach (see also Tiered Electric Rate structure and System Sizing). Also, if you oversize your system you will pay for a larger system, but will not get any benefit for producing more than you use (I'll address this in a future entry).

In the simplest terms, the amount of electricity that your Solar Electric system generates is subtracted off your electric bill. For example, if you use 700kWh's per month on average and your system generates 600kWh's per month on average then you will pay the utility company for the difference of 700kWh - 600kWh = 100kWh. This will put you into the lower priced tiers for electricity (Tiered Electric Rate structure) and significantly lower your electric bill.

Robert Morse
BSEE, MSEE
SunCal Solar, Incorporated
www.SunCalSolar.com