Net metering allows residential electric customers to generate their own power using small-scale renewable energy systems. Any excess power that customers produce goes back to their utilities, essentially running their electric meters backwards. Customers then get a credit on their electric bill.

The bill allows a simple 10-day registration process for systems with capacities up to 10 kilowatts. Last year, that process was only available for systems half that size. Typical home solar systems are around 7 kilowatts. This bill also clarifies how utilities should calculate the extra six cents per kilowatt hour that people with solar net metering systems receive for the excess energy they produce.

Rep. Margaret Cheney, D-Norwich, who is vice chair of the House Committee on Natural Resources and Energy, said the bill will help clarify the benefits of net metering and simplify the process for slightly larger systems. It will also promote more renewable energy generation, she said.

“It is having real results,” Cheney said. “More small renewable energy systems are going up as a result of net metering laws.”

Vermont has allowed net metering since 1998, when it passed the first law allowing the practice.

The current law also addresses a controversy over net metering that has persisted over the years. It requires the Department of Public Service to issue a report analyzing whether and to what extent net metering systems are subsidized by other retail electric customers. The report is due Jan. 15, 2013.

Utilities and some ratepayers have raised concerns that customers with net metering systems are being subsidized by other customers.

Eric Werner, general manager of Hardwick Electric Department, said the small utilities in particular have concerns with net metering and the costs that are shifted to standard ratepayers.

The issue, Werner said, is when net metered customers provide power back to the grid because they produce more than they use, they receive retail rates for it. For example, a retail rate for electricity could be 18 cents per kilowatt-hour, but the utility pays 10 cents. The gap between retail and what the utility pays the generators of large-scale electricity is what pays for things like infrastructure upgrades and running the utility. Net metered customers, Werner said, can then use the grid but not contribute to the costs to maintain it.

“A lot of the issue is that net metered customers are getting an advantage, and costs are shifted to other customers,” Werner said.

Another issue, Werner said, is that installing things like solar systems generally requires a few thousand dollars, so the people who are getting the advantage generally have more money. For smaller utilities in particular, he said, net metering requires a large amount of time for staff to calculate the billing for customers with these renewable energy systems.

Cheney said the counter-argument to the subsidy argument is that all the small distributive generation provides a benefit to the entire state by alleviating utilities from having to make more capital investments. She said the study required in the new bill will hopefully put the debate to rest.

“If there does turn out to be a cost to ratepayers, we’ll do something about it,” Cheney said.

The bill still needs to go through a third reading and pass through the Senate.

Correction: This story originally stated that this year’s net metering bill will give people with solar net metering systems six cents more per kilowatt hour of excess solar energy. It will actually clarify how utilities calculate that extra six cents.

As I commented on the White House ‘Wall’: This is great that you announced a federal investigation into Wall Street. Now … to see you actually DO the right thing for the AVERAGE person in this country and make the wealthy oil companies give back to our country and pay their share of taxes and return the unfair rebates that the IRS has given them. Absurd! If they paid their fair share, our country would definitely be on the road out of debt – and one of the worst thing is that they most of them aren’t willing to do the fair thing and that they even accept the ‘bennies’ they have been receiving!

Why do they even NEED all of their trilions of $? 
It won’t do them one bit of good if you don’t ‘G.E.T.’ one VERY important thing you sure got wrong in your speech, which is regarding CLEAN ENERGY! Clean energy does NOT include offshore drilling, gas fracking or coal. This will only keep the big oil companies happy. I have to consequently question your sincerity about Clean Renewable Energy, which should be one of your top concerns, along with getting our CO2 emissions. If this does not get under control by 2017, the IEA has warned the world that we are in BIG trouble – it will be too late to turn things around. Life cannot survive at 129º as Pakistan endured this past summer – take note of just this winter’s warmth in the whole northern part of our country and lack of snow. Snow means water for the rest of the year for places like Reno, NV, from Lake Tahoe – for example…

We need your help, Mr. President! 
And while we are on the subject – Where is that Solar that was supposed to be installed back on the White House, any way? Why have we not heard any more about that?

One more concern, Dear Mr. Obama: What are your plans for reducing our emission levels from the two worst offenders: Transportation and leaking under-insulated buildings that are wasting fossil fuel and sending the emissions off into our atmosphere, just adding to the problem?  These should be on your list of top infrastructures to change immediately – or at least working on feverishly…  No problems – only solutions!

In case you missed it or would like to watch last night’s ‘State of the Union Address’ , here it is:

Governor Peter Shumlin is thinking big. His comprehensive energy plan calls for Vermont to receive 90% of its energy from renewable sources by 2050. This is an amazing goal for our state. If implemented, this plan would make the Green Mountain State a leader in clean energy and an example for the rest of the country. Vermont can do this — but the governor needs your support.

Tell Governor Shumlin and key lawmakers that you support this comprehensive energy plan.

It is a bold plan. In addition to the 90% renewable goal for 2050, the governor wants our state to get 75% of electricity from renewable sources within 20 years. We can’t let this opportunity get away. We need to speak out and let the governor know that he has the support it takes to make this happen.

Show your support today for a greener Green Mountain State!

Investing in renewable energy means cleaner air. It means fighting climate change. It means more jobs for our state. This is a historic chance for Vermont to lead the charge towards a cleaner, greener future.

As Vermonters, let’s tell the governor that we stand with him to do tough things and get this done. Let’s show him that momentum is on the side of clean energy. Our future depends on it.

Thanks,

David Van Deusen
Conservation Organizer
Sierra Club

Tell Governor Shumlin: We Support Your Plan!

TAKE ACTION TODAY!

How you can help:
1. Share this with your social network using Facebook and Twitter.
2. Copy and paste the following into a new email to friends:
Dear Friends,
I just told Governor Shumlin that I support his bold plan to move Vermont to 90% renewable energy by 2050. This will make Vermont a leader in clean energy and green jobs. We need to show the governor he has the support he needs to make this a reality.

Send a message of support today!

Find out more and send your message here: http://www.greenenergytimes.org/?p=3776 To all or our readers: “Let’s get the recognition we deserve for setting the example for our country. Take a moment to vote for these two awards that we are cited to possibly receive. As Bill McKibben often says: ‘Onward and Forward’!”      ~ Green Energy Times

Renewable Energy World, a global online magazine for renewable energy has nominated two Vermont initiatives for their 2012 Reader’s Choice Awards. You can help Vermont gain national recognition by take just a few seconds to vote for one of these great initiatives!

The winner will receive the Readers’ Choice Award at the Excellence in Renewable Energy Awards ceremony, which takes place during the Renewable Energy World North America Conference & Expo in Long Beach, California from February 14-16, 2012.

First-in-the-Nation Solar Registration

REV and partners were phenomenally successful during last years’ legislative session with the passage of the Vermont Energy Act of 2011. Part of the energy act included the passage of a solar registration provision making it quicker and easier to install small-scale solar photovoltaic systems in Vermont.

The new solar registration process, which replaces permitting allows solar customers to install the system 10 days after completing a registration form and certificate of compliance with interconnection requirements. The Vermont timeline is among the fastest in the nation.

Click here to vote for this innovation in renewable energy policy.

Sheffield Wind

This past October Vermont celebrated the commissioning of its second and largest wind power facility. REV Member First Wind unveiled its 40 megawatt (MW) wind project in Sheffield, VT which will produce enough electrical energy for the whole of Caledonia County. The goal of the Sheffield Wind project is to deliver clean, renewable wind energy that will not only provide natural power to Vermonters, but also generate other benefits for the local community. Developed, owned and operated by First Wind, Sheffield Wind delivers a clean energy alternative to Vermont utilities to help stabilize energy costs.

Click here to vote for this fantastic example of Vermont’s leadership in renewable energy.

Thanks for your support and taking the short time to cast your votes! REV looks forward to working with you in 2012 to continue to strengthen the renewables and efficiency community in the state.

gabrielle@revermont.org
(802) 229-0099

www.REVermont.org

Vermont’s two largest utilities – Green Mountain Power and Central Vermont Public Service – are suing Entergy Corp. over the 2007 and 2008 cooling tower collapses at the Vermont Yankee nuclear power plant.

The lawsuit, filed in Vermont Superior Court in Windham County, accuses Entergy of costing the two utilities $6.6 million to buy power elsewhere when the plant shut down after the tower failures, GMP spokeswoman Dorothy Schnure said.

Entergy could have prevented that by doing more hands-on inspection of the towers, Schnure said. Entergy failed to enact common practices used in the nuclear industry, she said.

The U.S. Nuclear Regulatory Commission determined that the first tower failure was a result of over-tightened bolts and salt and mold degradation that went undetected, the utilities said.

On Aug. 27, 2007, the plant reduced power for 11 days because of the tower collapse, according to a news release from the two utilities.

In July 2008, the plant reduced power for 12 days following a second collapse, the utilities said.

Steve Costello, spokesman for CVPS, said the two utilities have tried to obtain compensation from Entergy without success. With the statute of limitations nearing expiration, he said, the companies filed the lawsuit.

Vermont Yankee spokesman Larry Smith said the company would have no comment because it is pending litigation.

Vermont Yankee is the subject of another lawsuit that is expected to yield a ruling any day now. Entergy is suing Vermont, challenging the state’s authority to shut the plant down when its certificate of public good expires in March.

The two utilities’ contracts for power from Vermont Yankee end in March and regardless of what happens with Entergy’s lawsuit against the state, will no longer receive power from the plant after that.

We have until 2017! That is FIVE years!!! FIVE!!! The whole world is at stake – nut just Africa!

Tears run down my face in fear – yet we MUST stay strong and Get IT DONE!

What are YOU… yes, YOU doing – not your neighbor?  Don’t wait until it is too late!

Do you even know what to do? Where to start? The answer lies within our Transportation, Buildings, which are the two worst offenders to our emission levels.

Please Don’t drive unless it is absolutely necessary. Never Idle. Car and Van Pool, Use Rideshare to connect!  In Vermont: www.ConnectingCommuters.org  (800-685-RIDE) or www.uppervalleyrideshare.com (802-295-1824 x204). Take the bus, train, ferry, bike, e-bike, walk, ski… and drive energy efficient vehicles. Our future transportation infrastructure needs to start now!

Seal and Insulate your Buildings to reduce the emissions caused from the use of dirty non-renewable fossil fuels. You can’t seal them tight enough!  Zero Energy Buildings ARE achievable. This should be the goal and not to settle for anything less!

Renewable Energy – this is the solution! Clean energy from Solar, Wind, Micro-hydro*…  We need Community Solar and Wind Farms… We can’t get solar installed or wind turbines up fast enough!  It is about TIME!  NOW is the time to G.E.T. going!

Learn more in every issue of Green Energy Times… New Issue coming out on Dec. 15th with a Front page article about the 2017 dilemma directly from the IEA warning, that Anjali Appadurai refers to … The new issue will be online next week, so ck back with us! AND, watch for G.E.T.  at newstands near you or subscribe on this website out and about in VT and NH at the same time!

* Micro-hydro is an untapped goldmine of energy producing power that runs 24 hrs a day and does NOT harm the environment in ANY way. The Federal Gov’t is the only block in making this happen.  It is time to get that changed.  Go to your state representatives and government officials and let’s get the micro-hydro laws changed!

Governor Shumlin sums it all up in his welcoming talk to all of those that attended the event.

Green Energy Time’s was there to talk to the owners of SameSun Solar, Phillip and Marlene Allen, and to learn what they are all about.  We have in our midst, a great new company that is helping to grow jobs by creating this progressive business. They will be able to help our state to create a clean energy future. Congratulations to the Allens and we wish you a very successful future in Rutland.

As Governor Shumlin said: “And Vermont is moving faster than most!” in this direction.

One of the announcements at the gathering was for Alderman’s Chevrolet of Rutland, who will be installing a solar system that is 15% larger that CVPS’s! The governor predicts that within a decade, Alderman’s will be selling more plugin’s than fill-ups there in the first solar city in America!

Solar PV Leads Small Town into Solar Big Leagues

November 19, 2011    By Paul Gipe

After only three years of development, a small town in Florida has moved into the ranks of the solar big leagues worldwide.

The municipal utility serving Gainesville, Florida expects that by year end 2011 the town will have installed 7.3 MW of solar photovoltaic (solar PV) systems.

The university town was one of the first in the US to implement a feed-in tariff for solar PV after a previous program using grants, tax credits, and net metering had failed to install any significant number of systems.

Gainesville Regional Utilities serves a population of 200,000 people. Thus, the utility’s feed-in tariff program has resulted in the installation of 0.036 kW per person. This is equivalent to that in California which has had various programs for solar PV in place since the early 2000s.

However, Gainesville will have to increase its installation rate 20 times to catch up with the German state of Bavaria, which is the region with the world’s highest concentration of solar PV of 0.60 kW per person. Puglia Italy is not far behind Bavaria with 0.49 kW per person.

By year end, solar systems in Gainesville will be generating nearly 1.5 million kWh per month. In 2011, the utility estimates solar PV will have generated nearly 10 million kWh.

The Gainesville feed-in tariff program has been modified annually since its introduction to reflect the falling costs of solar PV and to more equitably distribute installations across all ratepayer classes.

More than one-third of the installed capacity has been installed on rooftops in projects less than 100 kW in size.

~ End ~

This feed-in tariff news update is sponsored by the , An Environmental Trust, and the David Blittersdorf Family Foundation in cooperation with the Institute for Local Self-Reliance. The views expressed are those of Paul Gipe and are not necessarily those of the sponsors.

Paul Gipe
661 325 9590, 661 472 1657 mobile
pgipe@igc.org, www.wind-works.org

Concentrating Solar Power

One advantage of parabolic trough power plants is their potential for storing solar thermal energy to use during non-solar periods and to dispatch when it’s needed most. As a result, thermal energy storage (TES) allows parabolic trough power plants to achieve higher annual capacity factors—from 25% without thermal storage up to 70% or more with it.

Parabolic trough thermal energy storage technology includes:

• Storage systems
  • Two-tank direct
  • Two-tank indirect
  • Single-tank thermocline
• Molten-salt heat transfer fluid
• Storage media
  • Concrete
  • Phase-change materials

Thermal Energy Storage Systems

Two-Tank Direct

The first Luz trough plant, SEGS I, included a direct two-tank thermal energy storage system with 3 hours of full-load storage capacity. This system simply used the mineral oil (Caloria) heat transfer fluid (HTF) to store energy for later use. It operated between 1985 and 1999 and was used to dispatch solar power to meet the Southern California Edison winter evening peak demand period (weekdays between 5-10 p.m.).

Because power plants later moved to higher operating temperatures for improving power cycle efficiency, they also switched to a new higher temperature heat transfer fluid—a eutectic mixture of biphenyl-diphenyl oxide (Therminol VP-1 or Dowtherm A). Unfortunately, this fluid has a high vapor pressure. Therefore, it cannot be used in the same type of large unpressurized storage tank system similar to the one used for SEGS I.

Pressurized storage tanks are very expensive. They cannot be manufactured at the large sizes needed for parabolic trough plants.

Two-Tank Indirect

In recent years, a new indirect thermal energy storage (TES) approach has been developed. This approach takes advantage of the experience with the storage system used in the Solar Two— a molten-salt power tower demonstration project—and integrates it into a parabolic trough plant with the conventional heat transfer fluid through a series of heat exchangers.

The thermal energy storage system is charged by taking hot, heat transfer fluid (HTF) from the solar field and running it through the heat exchangers. Cold molten-salt is taken from the cold storage tank and run counter currently through the heat exchangers. It’s heated and stored in the hot storage tank for later use. Later, when the energy in storage is needed, the system simply operates in reverse to reheat the solar heat transfer fluid, which generates steam to run the power plant. It’s referred to as an indirect system because it uses a fluid for the storage medium that’s different from what’s circulated in the solar field.

Several parabolic trough power plants under development in Spain plan to use this thermal energy storage concept. For future parabolic trough power plants, a number of alternative approaches are being considered for reducing the cost of the thermal energy systems.

A two-tank indirect thermal energy storage system is relatively expensive—its primary disadvantage. The expense is due to the heat exchangers and the relatively small temperature difference between the cold and hot fluid in the storage system.

For more information, see our publications on two-tank indirect thermal energy storage systems.

Single-Tank Thermocline

A single tank for storing both the hot and cold fluid provides one possibility for further reducing the cost of a direct two-tank storage system. This thermocline storage system features the hot fluid on top and the cold fluid on the bottom. The zone between the hot and cold fluids is called the thermocline.

A thermocline storage system has an additional advantage—most of the storage fluid can be replaced with a low-cost filler material. Sandia National Laboratories has demonstrated a 2.5-MWhr, backed-bed thermocline storage system with binary molten-salt fluid, and quartzite rock and sand for the filler material.

Depending on the cost of the storage fluid, the thermocline can result in a substantially lower cost storage system. However, the thermocline storage system must maintain the thermocline zone in the tank, so that it does not expand to occupy the entire tank.

For more information, see our publications on thermocline systems.

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Direct Molten-Salt Heat Transfer Fluid

Using molten-salt in both the solar field and thermal energy storage system eliminates the need for expensive heat exchangers. It allows the solar field to be operated at higher temperatures than current heat transfer fluids allow. This combination also allows for a substantial reduction in the cost of the thermal energy storage (TES) system.

Unfortunately, molten-salts freeze at relatively high temperatures 120 to 220°C (250-430°F). This means that special care must be taken to ensure that the salt does not freeze in the solar field piping during the night.

The Italian research laboratory, ENEA, has proven the technical feasibility of using molten-salt in a parabolic trough solar field with a salt mixture that freezes at 220°C (430°F). And Sandia National Laboratories are developing new salt mixtures with the potential for freeze points below 100°C (212°F). At 100°C the freeze problem is expected to be much more manageable.

For more information, see our publications about molten-salt heat transfer fluid.

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Thermal Energy Storage Media

Concrete

The German Aerospace Center (DLR) is examining the performance, durability and cost of using solid, thermal energy storage media (high-temperature concrete or castable ceramic materials) in parabolic trough power plants.

This system uses the standard heat transfer fluid (HTF) in the solar field. The heat transfer fluid passes through an array of pipes imbedded in the solid medium to transfer the thermal energy to and from the media during plant operation.

The primary advantage of this approach is the low cost of the solid media. Primary issues include maintaining good contact between the concrete and piping, and the heat transfer rates into and out of the solid medium.

At the Plataforma Solar de Almeria in Southern Spain, Ciemat and DLR performed initial testing that found both the castable ceramic and high-temperature concrete suitable for solid media, sensible heat storage systems. However, the high-temperature concrete is favored because of lower costs, higher material strength, and easier handling. There is no sign of degradation between the heat exchanger pipes and storage material.

DLR has also developed a design tool that helps optimize the storage layout, including the geometric dimensions and piping and module arrangement to minimize pressure losses and optimize manufacturing aspects and costs.

Because of the modular nature of concrete storage, DLR has identified approaches that allow the storage system to better integrate with the solar field and power cycle. This allows for improved overall utilization of the concrete storage system. DLR is also testing a new, more optimized concrete storage module at the University of Stuttgart.

Phase-Change Materials

Phase-change materials (PCMs) allow large amounts of energy to be stored in relatively small volumes, resulting in some of the lowest storage media costs of any storage concepts.

Initially phase-change materials were considered for use in conjunction with parabolic trough plants that used Therminol VP-1 in the solar field. Luz, and later ZSW, proposed an approach that used a cascading set of phase-change materials to transfer heat from the heat transfer fluid (HTF). In this approach, thermal energy transfers to a series of heat exchangers containing phase-change material that melt at slightly different temperatures. To discharge the storage, the heat transfer fluid flow is reversed. This results in reheating of the heat transfer fluid.

Although testing proved the technical feasibility of this system, further development of the concept was hindered because of the:

• Complexity of the system
• Thermodynamic penalty of going from sensible heat to latent heat and back to sensible heat
• Uncertainty over the lifetime of phase-change materials.

More recently DLR is evaluating phase-change thermal energy storage for application with direct steam generation in the parabolic trough solar field. This allows for a better thermodynamic match between the phase-change material and the phase-change of steam used in the solar field. In this approach a single phase-change material can be used to preheat, boil, and superheat steam. DLR has found that the cost of the system is driven not only by the cost of phase-change storage material, but also by the rate at which energy will be charged or discharged from the material.

Also, DLR has developed a graphite foil that it uses to sandwich the phase-change material for increasing heat transfer rates. Lab scale tests of this approach have demonstrated its feasibility. And future tests will be integrated into the DISS facility at the Plataforma Solar de Almeria.

For more information, see our publications about phase-change materials.