Wednesday, June 30, 2010

High Production but High Usage Too

This is the time of year when it's hard to tell if my system is making any difference at all. Ironically, it's the part of the year when it generates the most power (longest periods of high-sky sun) so you'd think it would be the most interesting time for watching it go. But as I've already detailed ad nauseum, it's also the part of the year where I use the most power -- because the evil air conditioner and it's partner in crime, the insidious pool filter -- are running a lot.

Checking the electric meter during the summer just isn't as exciting as it is in April or October because it's not spinning backwards as much.

Luckily I can look at the inverters and see that a lot of power is being generated. Now I remember why I spent so much time checking those last summer...

Wednesday, June 16, 2010

Guest Blogger Today

We have a guest blogger today. Barbara Young has a lot of interesting and informative things to tell us about solar energy: how it works, some history, and a really thorough list of solar power pros and cons.

Warning from Dave -- she knows way more about solar power than I do -- get ready to learn!

Barbara writes regularly here on her very lively site that I plan to keep up with:

Her efforts are focused entirely on helping people save energy using solar powered energy to reduce CO2 emissions and energy dependency.

After you read this I’m betting that you bookmark that site – it’s that good!


Here’s an instant approach to learn the way solar panels work

What's solar energy ?

Solar energy is radiant energy that's produced by the sun. Each day the sun radiates, or sends out, an enormous amount of energy. The sun radiates more energy in one second than people have used since the beginning of time!

The energy of the Sun derives from within the sun itself. Like other stars, the sun is mostly a big ball of gases––mostly hydrogen and helium atoms.

The hydrogen atoms in the sun’s core combine to create helium and generate energy in a process called nuclear fusion.

During nuclear fusion, the sun’s extremely high pressure and temperature cause hydrogen atoms to come apart and their nuclei (the central cores of the atoms) to fuse or combine. Four hydrogen nuclei fuse to become one helium atom. However the helium atom contains less mass compared to four hydrogen atoms that fused. Some matter is lost during nuclear fusion. The lost matter is emitted into space as radiant energy.

It requires millions of years for the energy in the sun’s core to make its way to the solar surface, and then slightly over eight minutes to travel the 93 million miles to earth. The solar energy travels to the earth at a speed of 186,000 miles per second, the speed of sunshine.

Only a small part of the energy radiated by the sun into space strikes the earth, one part in two billion. Yet this quantity of energy is enormous. On a daily basis enough energy strikes the united states to supply the nation’s energy needs for one and a half years!

Where does all this energy go?

About 15 percent of the sun’s energy that hits the planet earth is reflected back to space. Another 30 percent is used to evaporate water, which, lifted in to the atmosphere, produces rainfall. Solar energy is also absorbed by plants, the land, and the oceans. The remaining could be employed to supply our energy needs.

Who invented solar power ?

People have harnessed solar technology for hundreds of years. Since the 7th century B.C., people used simple magnifying glasses to concentrate the light of the sun into beams so hot they would cause wood to catch fire. Over 100 years ago in France, a scientist used heat from a solar collector to produce steam to drive a steam engine. In the beginning of this century, scientists and engineers began researching ways to use solar energy in earnest. One important development was obviously a remarkably efficient solar boiler invented by Charles Greeley Abbott, an American astrophysicist, in 1936.

The solar hot water heater gained popularity at this time in Florida, California, and the Southwest. The industry started in the early 1920s and was in full swing prior to The second world war. This growth lasted before mid-1950s when low-cost natural gas took over as primary fuel for heating American homes.

People and world governments remained largely indifferent to the possibilities of solar energy before oil shortages of the1970s. Today, people use solar technology to heat buildings and water and also to generate electricity.

How do we use solar power today ?

Solar energy is employed in several different ways, of course. There are two very basic kinds of solar energy:

* Solar thermal energy collects the sun's warmth through 1 of 2 means: in water or in an anti-freeze (glycol) mixture.
* Solar photovoltaic energy converts the sun's radiation to usable electricity.
Listed here are the five most practical and popular ways that solar energy is employed:

1. Small portable solar photovoltaic systems. We have seen these used everywhere, from calculators to solar garden tools. Portable units can be utilised for everything from RV appliances while single panel systems are used for traffic signs and remote monitoring stations.

2. Solar pool heating. Running water in direct circulation systems via a solar collector is an extremely practical method to heat water for your pool or hot tub.

3. Thermal glycol energy to heat water. In this method (indirect circulation), glycol is heated by natural sunlight and the heat is then transferred to water in a warm water tank. Using this method of collecting the sun's energy is more practical now than ever. In areas as far north as Edmonton, Alberta, solar thermal to heat water is economically sound. It can pay for itself in three years or less.

4. Integrating solar photovoltaic energy into your home or business power. In many parts on the planet, solar photovoltaics is an economically feasible method to supplement the power of your home. In Japan, photovoltaics are competitive with other types of power. In the USA, new incentive programs make this form of solar technology ever more viable in many states. An increasingly popular and practical way of integrating solar energy into the power of your home or business is through the usage of building integrated solar photovoltaics.

5. Large independent photovoltaic systems. For those who have enough sun power at your site, you might be able to go off grid. You may also integrate or hybridize your solar energy system with wind power or other forms of renewable energy to stay 'off the grid.'

How can Photovoltaic panels work ?

Silicon is mounted beneath non-reflective glass to produce photovoltaic panels. These panels collect photons from the sun, converting them into DC electrical energy. The power created then flows into an inverter. The inverter transforms the power into basic voltage and AC electrical energy.

Solar cells are prepared with particular materials called semiconductors for example silicon, which is presently the most generally used. When light hits the Photovoltaic cell, a certain share of it is absorbed inside the semiconductor material. This means that the energy of the absorbed light is given to the semiconductor.

The power unfastens the electrons, permitting them to run freely. Photovoltaic cells also have one or more electric fields that act to compel electrons unfastened by light absorption to flow in a specific direction. This flow of electrons is a current, and by introducing metal links on the top and bottom of the -Photovoltaic cell, the current can be drawn to use it externally.

What are the positives and negatives of solar energy ?

Solar Pro Arguments

- Heating our homes with oil or natural gas or using electricity from power plants running with oil and coal is a reason for global warming and climate disruption. Solar power, on the other hand, is clean and environmentally-friendly.
- Solar hot-water heaters require little maintenance, and their initial investment can be recovered within a relatively short time.
- Solar hot-water heaters can work in nearly every climate, even in very cold ones. Simply choose the best system for your climate: drainback, thermosyphon, batch-ICS, etc.
- Maintenance costs of solar powered systems are minimal and the warranties large.
- Financial incentives (USA, Canada, European states…) can aid in eliminating the cost of the first investment in solar technologies. The U.S. government, for instance, offers tax credits for solar systems certified by by the SRCC (Solar Rating and Certification Corporation), which amount to 30 percent of the investment (2009-2016 period).

Solar Cons Arguments

- The initial investment in Solar Hot water heaters or in Solar PV Electric Systems is higher than that required by conventional electric and gas heaters systems.
- The payback period of solar PV-electric systems is high, as well as those of solar space heating or solar cooling (only the solar warm water heating payback is short or relatively short).
- Solar water heating do not support a direct in conjunction with radiators (including baseboard ones).
- Some air conditioning (solar space heating and the solar cooling systems) are costly, and rather untested technologies: solar ac isn't, till now, a truly economical option.
- The efficiency of solar powered systems is rather influenced by sunlight resources. It's in colder climates, where heating or electricity needs are higher, that the efficiency is smaller.

Sunday, June 13, 2010

Several Newspaper Articles This Weekend

From Diane Mastrull of the Philadelphia Inquirer, Saturday

Pa. Quietly takes back its solar-energy tax credit

"For a state that says it's trying to encourage more alternative-energy use, this is not an especially proud development. Which may explain why Pennsylvania put out no news releases and held no news conferences about it."

Dave's comment: I'm sorry to see this, but solar energy subsidies are frills that are hard to make cases for in the current state of affairs.


From Jacqueline L. Urgo of the Philadelphia Inquirer, Saturday

Historic Cape May Allows Newfangled Alteration

"Thirty-eight new solar panels are hidden from sight atop the ornate 1882 Italianate structure that houses the Mad Batter Restaurant and Carroll Villa Hotel in the historical heart of this 19th-century seaside town."

Dave's comment: Cool. I'm glad they found a way to preserve the Cape May image while making room for progressive change.


From Eileen Smith of the Courier-Post (South Jersey's biggest paper!), Sunday

Solar Energy is Hot in N.J. -- Generous rebates pay dividends for homeowners

"New Jersey has the best economics in the country for solar," said David Lloren, CEO of San Francisco-based One Block off the Grid (1BOG), a broker for residential installation services.

Dave's comment: Ha! I'm going to generate at least twelve SRECs a year, not the paltry seven estimated in this article. But even so, my estimate for payback is 3.5 - 4 years, not the optimistic 2.8 years projected here.

Friday, June 11, 2010

Terminology, Calculations, etc.

The other day I had a question that really, at this point I should have been able to answer easily. I couldn't. It involved a really basic principle: if a system is rated as size X, how much power does it produce?

Here's a useful web site developed by people who aren't as clueless as me:

Solar & Wind Energy Calculations: The (very) Basics

This paragraph from that website helped me the most because it explains what a system size rating means over the course of time (which was the concept I proved to be not too bright about):

"One kilowatt-hour (1 kWh) means an energy source supplies 1,000 watts (1 kW) of energy for one hour. Generally, a solar energy system will provide output for about 5 hours per day. So, if you have a 1.8 kW system size and it produces for 5 hours a day, 365 days a year: This solar energy system will produce 3,285 kWh in a year (1.8 kW x 5 hours x 365 days)."

One blog reader says this on June 15: "Actually 1000 kW of DC system produces about 1200 kWh of AC electric."

Wednesday, June 9, 2010

I'm a Solar Incentive Hypocrite

Remember the other day when I posted that I have mixed feelings about the government programs that I have benefited from? Here's what I meant.

On the one hand I think we need to look forward and exploit new technologies to generate the energy we need. On the other hand -- I'm just not a big government guy.

The word "hypocrite" won't get out of my head.

Below is a link to an interesting column by David Levy of The Energy Collective. It includes this quote:

"...This is a massive subsidy indeed, and raises significant policy issues. Even for those who are fervent advocates of renewable energy, does it make sense to provide such huge subsidies to solar, when modest subsidies for land-based wind power of around 2-3c/kWh serve to make it grid competitive in many regions? Would the money be better spent on research and development, and the development of local workforce skills and business clusters? Subsidizing installation at the retail level will generate a few local jobs for developers, electricians and installers, but the panels will mostly be imported. There is a serious risk of consumer backlash when people realize the extent of the subsidies and the impact on their utility bills..."

David Levy Column

Just food for thought, my friends...

Tuesday, June 8, 2010

Only 2 KWH Bought From PSE&G in March

Here's a snippet of my latest electric bill:

It turns out that I won't be receiving many exciting (negative) electric bills for a while because PSE&G does a lot of estimations (which you can see here).

I have to take a really close look to see the exciting stuff. If you look at the March row of this table you can see that in March 2009 I bought 760 KWH hours of power. In March 2010 it was only -- [drum roll] -- 2 KWH.

That's kind of cool. March wasn't even really very sunny. We didn't even generate an entire SREC. April will be more exciting -- unless PSE&G estimates the excitement away.

Monday, June 7, 2010

SRECs Sold So Far

As a review: an SREC is a certification that a system has produced 1000 Kilowatthours of solar energy. They can be bought and sold as commodities. In most states the utility companies are required to include certain percentages of 'green' power in their total production. They can and do purchase these certificates rather than physically generate the green power to meet this requirement. [I have mixed feelings about this scheme, many of which make me a hypocrite, but that's for another post.]

We sold one SREC for May, for $ 665.

So here's summary of SREC activity. We've been eligible to generate them since sometime last fall (I haven't been able to pin down the exact point where the energy we generated "counted" but I know we lost out on all that summer 2009 power because we hadn't passed inspection yet.)

Fall 2009 (sold at auction in December): 4 SRECs @ $ 660 = $ 2640
December 2009 (none generated)
January 2010 (sold at auction in February): 1 SREC @ $ 660 = $660
February 2010 (sold at auction in March): 1 SREC @ $ 665 = $ 665
March 2010 (none generated)
April 2010 (sold at auction in May): 2 SRECs @ 665 = $ 1330
May 2010 (sold at auction in June): 1 SREC @ 665 = $ 665

Grand Total: 9 SRECs sold for a total of $5,960.

Friday, June 4, 2010

Happy Anniversary

Well today is anniversary day! One year ago today the system was completed and went online.

Also, it's Happy 22nd Anniversary to Dave and LA. Dinner at Guillermo's tonight to celebrate...

Wednesday, June 2, 2010

Different Kinds of SREC Brokers Out There!

I've been getting lots of questions from people who are signing up with SREC brokers who are offering deals which, let's say, aren't as good as the one I have. Immediately below I answered three questions that came in today. Then, rather than retype the same sentiments, I went back through my comments and dug up my best answer.

I apologize in advance for loving my broker, SRECTrade!

This question is from Jim in a comment posted today (June 2, 2010).

From your post, you are located in New Jersey. I have just received a proposal from my 'installer/broker' for a commission that is far greater than what you seem to be paying.

I have 3 questions:

1.) Are you receiving current (2010) market value for your SRECS?

Dave's answer: Yes. I sell my SRECS (well, my broker does ALL the work) every month at auction so I get the 2010 New Jersey market value (it's always been $660 or $665 so far.)

2.) How often are you making your SRECs available to the market? Monthly? quarterly?

Dave's answer: My SRECs sell in an auction every month.

3.) Regarding the paperwork - did you have all the information required readily available to you or did you have to dig for it?

Dave's answer: Once I signed on with my broker (SRECTrade) and filled out about 3 pages of forms that they sent, they did everything. I just sit back and wait for direct deposit.

Here's a more in-depth answer, which I copied from an older comment trail in the "1040 Good Buddy" post:

note: this reply will sound like a commercial for SRECTrade, the broker that handles my SRECs. I'm not associated with them in any way except as a customer -- but the fact is that they rock and I'm glad to endorse their services.]

First of all, don't worry about your SREC rotting away. You have plenty of time to decide how to sell these things.

I did research and decided to work with SRECTrade. I think they're fantastic. They'll hold your hand through signing up and all the red tape/paperwork. Then you can just sit back and read emails about the SRECs they've sold for you.

There are a lot of brokers out there. Some are like SRECTrade -- they take a very small commission and make their money by doing LOTS of transactions. With most of these, including SRECTrade, you are free to pull out of the arrangement any time.

The other ones are more old-fashioned. They don't want you to know the specifics, they just want you to commit to a long term arrangement (which usually benefits them a lot more than they benefit you, in my opinion.) My installer tried to push me into one of these. After I read the fine print I realized why -- they get a commission for the first two years of the contract. I thought it was a little shady.

Anyway, I am completely happy with SRECTrade. I can't imagine a better deal. I know it's possible to sell these on your own but the commission with SRECTrade is so small that I can't imagine going through all the hassle.

I hope I've helped. Feel free to ask me anything. I'm always happy to help!