• New Discovery Could Improve Organic Solar Cell Performance

    While there is a growing market for organic solar cells ­­– they contain materials that are cheaper, more abundant, and more environmentally friendly than those used in typical solar panels – they also tend to be less efficient in converting sunlight to electricity than conventional solar cells. Now, scientists who are members of the Center for Computational Study of Excited-State Phenomena in Energy Materials (C2SEPEM) a new Read More
  • Know Your Rights

    Arizona law protects individual homeowners’ private property rights to solar access by dissolving any local covenant, restriction or condition attached to a property deed that restricts the use of solar energy. This law sustained a legal challenge in 2000. A Maricopa County Superior Court judge ruled in favor of homeowners in a lawsuit filed by their homeowners association seeking to force the homeowners to remove Read More
  • Home Battery Systems

    Rooftop solar panels are common in Arizona thanks to abundant sunshine, but to get even more use from the technology, homeowners are beginning to pair them with large home batteries. Batteries allow homeowners to store their surplus electricity, rather than send it to the grid in exchange for credit from their electric company. Read More
  • Solar Hot Water

    There are two types of solar water heating systems: active, which have circulating pumps and controls, and passive, which don't. The typical solar water heater is comprised of solar collectors and a well-insulated storage tank. The solar collector is a network of pipes that gathers the sun's energy, transforms its radiation into heat, and then transfers that heat to either water or a heat-transfer fluid. Read More
  • Federal Residential Renewable Energy Tax Credit

    (Information provided by DSIRE - Last reviewed 02/19/2009) The information below is somewhat dated, the incentives have been extended, but reduced.  See our more up to date article. Incentive Type:   Personal Tax Credit State:   Federal Eligible Renewable/Other Technologies:   Solar Water Heat, Photovoltaics, Wind, Fuel Cells, Geothermal Heat Pumps, Other Solar Electric Technologies Applicable Sectors:   Residential Amount:   26% Maximum Incentive:   Solar-electric systems Read More
  • Solar Building Design in Arizona

    The idea of using the sun to meet the energy needs in our buildings has been with us since the time of the Greeks, with some of the design manifestations even evident in the prehistoric structures of Arizona and the Southwest. There is a great historic tradition for Arizona buildings that utilize our most abundant resource, and the current increases in The idea of using Read More
  • How Not to- Battery Connections

    Photo shows the situation after a battery discharge test at 300 amps was terminated on a 1530 AH IBE battery string when one post melted. During the discharge test all cell voltages are logged. The sum of the cell voltages was 2.73 volts lower than the 48-volt string voltage. This is an average of 118 mv per inter-cell connection, 5-10 mv is the normal range Read More
  • 1 New Discovery Could Improve Organic Solar Cell Performance
  • 2 Know Your Rights
  • 3 Home Battery Systems
  • 4 Solar Hot Water
  • 5 Federal Residential Renewable Energy Tax Credit
  • 6 Solar Building Design in Arizona
  • 7 How Not to- Battery Connections


  1. Solar Center Blog
Brian Czech
17 February 2019

What’s Really Green and What’s Really New

Ask Americans what the Green New Deal is all about, and you’ll get two basic answers. Most often you’ll hear, “It’s about moving to renewable energy in order to fight climate change.” You’ll also hear, from a camp further right, “It’s all about socialism!”

Lucy Mason
06 January 2018

Wishing you a wonderful and Happy New Year!

The year 2017 has gone by quickly, and AriSEIA has accomplished a full and active agenda to further solar and renewable energy in Arizona. 

Featured (Note- Articles below shift Left-Right)

Some things to pay attention to in Arizona

Arizona Legislature 

Not in session

Arizona Corporation Commission 

The Arizona Corporation Commission (ACC) has posted STAFF'S THIRD REVISED PROPOSED DRAFT RULES (DOCKET no. RE-00000A-18-0284) That lay out a clearer framework for Electric Utilities to report their compliance with the proposed standards for the Renewable Energy Standard, Clean Peak Standard, Distributed Renewable Storage Requirement, and Electric Vehicle Infrastructure.

See the ACC Staff Report: docket.images.azcc.gov/E000004960.pdf

See also Materials Presented by the Joint Stakeholders at the Commission's March 2020 Energy Rules Workshop

ACC Staff has made substantial changes to the draft rules that were filed on July 2, 2019 based on feedback received at each workshop held in this matter, comments to the docket, and a review of relevant energy policies across the United States.

The Nature Conservancy has submitted their report "Arizona Thrives - A Path to a Healthy and Prosperous Future" to the ACC. Interesting.

APS has submitted their report,  The Solar Center has slightly reformatted this report by rotating the pages for easier viewing.  APS has provided two presentations to address the ACC questions. Worth a read.

The Arizona Corporation Commission (ACC) has released the Notice of Final Rulemaking Interconnection of Distributed Generation FacilitiesInterconnection of Distributed Generation Facilities document.

With this rulemaking, the Commission adds a new Article 26, entitled " Interconnection. of Distributed Generation Facilities" to 14 A.A.C. 2, the Chapter containing the Commission's rules for fixed utilities, with the new Article 26 including 28 new rules. The rules for Interconnection of Distributed Generation Facilities ("DGI Rules") establish mandatory technical standards, processes, and timelines for utilities to use for· interconnection and parallel operation of different types of distributed generation ("DG") facilities; customer and utility rights and responsibilities; provisions for disconnection of DG facilities from the distribution system; specific safety requirements; more flexible standards for electric cooperatives; a reporting requirement; and a requirement for each utility to create, submit for initial approval and submit for approval periodically and when revised, and implement and comply with a Commission-approved Interconnection Manual.

The first dozen pages are basically legal stuff.  The document defines how an utility must review, then accept/reject/etc. an application to connect distributed generation to the utility.  It defines both customer rights and utility procedures.  There are a lot of utility, installer and customer comments along with the ACC staff recomendations. 

 Municipality Info


PhoenixFireLogo sm

The City of Phoenix is now (January 2020) requiring a special permit from the Fire Department for most solar systems and batteries.  The fees and required plans varies with size and content.  See this link for an application and details:  https://www.phoenix.gov/firesite/Documents/Solar Photovoltaic OTC Bundle Rev 01-2020.pdf

This is in addition to a building permit from the Planning & Development Department and must be separately obtained at a different address (150 South 12th Street) or on-line via the above link. Also noted is that residential PV permits are no longer over the counter and as of March 2020 are estimated to take 29 working days to process.  Separate inspections are required.

The code requirements are contained in Phoenix-Chapter 12 BESS R-3-1.pdf

Also note: All Phoenix solar building permits are now electronic submittal only. Contact the Electronic Plan Review (EPR) Triage Team at 602-534-5933 or epr.support@phoenix.gov. For more information on EPR, visit us at https://www.phoenix.gov/pdd/onlineservices/electronic-plan-review.


 At the Federal Level

The US House passed the Moving Forward Act, H. R. 2, on July 1, 2020. The US$1.5 trillion infrastructure support bill includes a raft of measures in support of America’s clean economy. The bill proposes to extend the solar Investment Tax Credit (ITC) scheme to 2025. Major resistance is expected in the Senate.

More details on this bill are at: Solar-friendly US infrastructure bill inches forward as it passes House

Additional coverage: House Democrats Spell Out Climate, Clean Energy Priorities in Sweeping Plan


Utility Information

Arizona Public Service Co. has announced that it plans to produce all of its electricity from carbon-free sources by 2050 and will get 45% of its power from renewable sources like solar and wind by the end of this decade.

This is a good improvement from the point of view of sustainable energy.  There are still a lot of details to be worked out such as the role that distributed energy will take.  Will APS APS improve its policies in regard to residential and small commercial systems.

There are several good news articles and the APS press releases on this announcement:

APS:APS sets course for 100 percent clean energy future

Arizona Republic: APS will eliminate carbon emissions by 2050 and close coal plant ahead of schedule, CEO says

The Washington Post: Arizona’s biggest utility says it will get all of its electricity from carbon-free sources by 2050


Tucson Electric Power (TEP) plans to provide more than 70 percent of its power from wind and solar resources as part of a cleaner energy portfolio that will reduce carbon emissions 80 percent by 2035.

TEP has filed its integrated resource plan (IRP) with the Arizona Corporation Commission, outlining plans for 2.5GW of new solar and wind over the next 15 years and 1.4GW of energy storage capacity as it progressively shutters its coal power stations.

See the TEP Press Release for more information: https://www.tep.com/news/tep-plans-clean-energy-expansion-carbon-reduction/

TEP customers intending to install a new PV system now need to check that their system can be safely installed and connected to TEP’s grid.

TEP now has service areas that are saturated with PV systems where new PV systems are subject to additional review and requirements under Arizona’s Distributed Generation Interconnection Rules. TEP has prepared DG Saturation Maps showing these areas.

This further described at https://www.tep.com/get-started-with-solar/

This requirement stems from the recent Distributed Generation Interconnection Rules issued by the Arizona Corporation Commission.

Further information is available at:Interconnection of Distributed Generation Facilities




Interesting Technology Updates;





Other Announcements


Interesting Videos

SEIA's Principles for the Evolution of Net Energy Metering and Rate Design

SEIA, AriSEIA, five other SEIA state affiliates, and 10 other organizations including Vote Solar have agreed upon general principles on how Net Energy Metering (NEM) and rate design should be implemented. The announcement was made on May 31, 2017. We present those principles below. The document provides a consensus view of solar advocates for regulators and stakeholders considering rate design and compensation for distributed solar generation, including potential alternatives to net energy metering.  Traditional net energy metering (NEM) is fundamentally a bill credit that represents the full retail value of distributed electricity delivered to the distribution system, and has been a critical policy for valuing and enabling distributed generation.  As penetration of solar and other distributed energy resources increases, states and utilities have begun to examine, and in some cases implement, alternative rate and compensation mechanisms.  The principles below are intended to be consistent with the imperative of public utility commissions and energy service providers to maintain reliable, cost-effective service to all customers while protecting the rights of customers to generate their own energy in a manner that provides both system and public benefits, including environmental protection and economic development.  They provide high level criteria for the conditions under which states may wish to consider alternatives to NEM, and high level principles for what distributed solar compensation mechanisms should look like where alternatives to NEM are appropriately considered. 

Specifically the paper is organized into four sections:

  • Basic principles, foundational to considerations for considering rate design and compensation for distributed solar generation.
  • Criteria and Conditions for the Consideration of Alternatives to Net Energy Metering
  • Guiding Principles for Solar Rate Design, and
  • Guiding principles for Alternative Compensation

Basic Principles[1]

  • Customers have a right to reduce their consumption of grid-supplied electricity with energy efficiency, demand response, storage, or clean distributed generation.  Thus, a customer should always receive the full retail price value for behind the meter choices that reduce grid-supplied energy consumption, whether installing energy efficiency measures, or consuming on-site generation.
  • Solar rate design and compensation mechanisms should support customer economics to invest in solar that are sustainable, consistent with the full stream of values provided by the system, and fair to all stakeholders.
  • Net energy metering is a proven mechanism for driving solar deployment, liked and understood by customers, and is preferred in most circumstances.
  • Most studies have shown that the benefits of distributed solar generation equal or exceed costs to the utility or other customers where penetration is low.  Assertions that current or future solar customers have shifted or will shift costs to others, and/or create new costs, must be demonstrated with valid, transparent data that reflects the values, avoided utility costs, and results of deploying solar at the distribution level, as well as the utility cost of providing service.
    • A cost of service study that fails to consider the benefits of distributed solar generation (DSG) cannot establish a cost-shift.
    • Regulators should require an independent cost-benefit analysis before considering substantial rate design or compensation changes based on cost-shift assertions.
    • The benefits of existing distributed solar should be recognized when considering any asserted cost shift.
    • The time frame for review of costs and benefits must be on par with the life of the particular type of Distributed Energy Resources (DER) assets, e.g. 20-30 years, and be forward looking, not a snapshot of one year of sunk costs as is typical in a general rate case (GRC).
    • Regulators should seek to ensure in GRC, Integrated Resource Plans (IRP) and other relevant proceedings that future avoided costs found in cost/benefit studies related to DSG and other DER are actually avoided (e.g. the canceled PG&E transmission projects saving $200 million and the Brooklyn-Queens Demand Management project avoiding costly upgrades).
    • Since some level of quantifiable cross-subsidization is inherent in all rate design, particularly for large diverse classes, an independent finding of a material cost shift should be required before regulators authorize substantial changes to rates or rate design.
  • Net metering can be accomplished through simple energy netting, or in combination with monetary compensation depending on the rate design:
    • For non-time differentiated residential and small commercial rates, i.e. rates based on energy consumed at any time, energy netting on a kWh basis over the billing period is good policy particularly at low to moderate penetration levels, and pending demonstration of a material impact.
    • For time-differentiated rates, monetary compensation is an accepted feature of some current NEM structures and may be necessary to preserve the full value of excess energy.
  • Opportunities for retail customers and third party DSG and other DER developers to provide additional services (e.g. voltage & frequency regulation, VAR support) should be encouraged, especially in States moving towards a service oriented utility/regulatory model, though access to markets, and appropriate compensation mechanisms.
  • Consideration of creating separate rate classes for customers that choose to utilize DER technologies must be based upon a factual demonstration of significantly different load and cost characteristics using publicly available actual data, and should generally be discouraged as potentially discriminatory.

Criteria and Conditions for the Consideration of Alternatives to Net Energy Metering

  • Penetration level should be the leading threshold criteria for consideration of alternatives to NEM.
  • Customers who installed solar under net metering should be grandfathered for a reasonable period of time. Customers have a reasonable expectation that rate structures (as opposed to rates themselves) will not change dramatically.  Gradualism is an important rate design principle, and a gradual phase-in to any new compensation methodology should be provided at the end of the grandfathering period.
  • Process: Early, i.e. pre-litigation, data collection and analysis under the guidance of the State Commission can provide opportunities for collaboration toward the development of a factual basis for future changes to rate designs, compensation, and other mechanisms. 
  • Simplicity, Gradualism, and Predictability: The simplicity of the NEM compensation mechanism facilitates customer adoption of distributed solar. Any future design should consider customer needs for simplicity and any changes should be applied gradually and predictably.
  • Shadow billing and voluntary pilot programs to analyze opportunities to increase the benefits that net metered systems provide to the grid, and to assess the actual impacts of proposed changes (for example, time-of-use (TOU) pilot programs) should be considered before making substantial mandatory changes to compensation or rate design. 
  • Hold harmless policies should be in place for low-to-moderate income (LMI) customers.
  • NEM imports & exports are generally netted monthly in most states, and trued up annually.  More granular netting generally reduces solar customer economics, but may be worthy of consideration when penetration levels increase, or in conjunction with deployment of other DERs such as storage.

Guiding Principles for Solar Rate Design

  • Rate design should seek to send clear price signals to customers that encourage sustainable, cost-effective investments in solar and complementary technologies.
  • Rate designs should not create barriers to the deployment of distributed solar generation or DER technologies other than solar.
  • Rate designs that provide greater incentives for DER technology deployment (e.g. more steeply inverted block rates) can be considered to encourage early adoption of efficiency, distributed generation and storage technologies.
  • Rate designs that emphasize temporal cost-causation (time-varying, critical peak pricing and critical peak rebates) are generally consistent with solar deployment, and may be quite beneficial to customer and system alike when solar is integrated with DERs like storage or demand response.
  • Rate designs that emphasize higher fixed (e.g. customer, service and facility or basic service) charges than necessary for recovery of strictly customer-related costs like service drop, billing, and metering, or quasi-fixed (e.g. mandatory residential demand) charges do not reflect cost causation, disproportionately impact low and moderate income customers, and should be discouraged.
  • Regulatory review of rate design alternatives should consider impacts on low-income customers; e.g. utility fixed or quasi-fixed charge proposals usually put solar and efficiency technologies further out of reach of LMI customers.
  • Any consideration of standby, backup or other supplemental charges for solar customers must (1) be consistent with PURPA requirements, (2) be based upon a customer’s ability to control self-generation similar to a conventional fossil resource (e.g. diesel or natural gas), and (3) reflect the probability of customer generation unavailability in the development of any rates.

Guiding principles for Alternative Compensation

A fair value of solar (or “stacked benefit”) compensation rate can be considered for distributed solar generation exports, at higher penetration levels. Such value should be determined taking into account both short term and long term (life of system) benefits of distributed solar generation. Buy all/Sell all (BA/SA or “VOST”) compensation approaches should be at the option of the retail customer, i.e. VOST should not be the only customer option.  Critical considerations impacting system economics and the ability to finance include the frequency and effect of future changes to the value proposition.  In addition, consideration must be given to the effect on customers of the lack of energy hedging (customer-generated solar energy does not offset the customer’s utility-supplied energy). Alternative Compensation methods should take into account the efficacy of integrating solar with other forms of DER (e.g. storage) in the grid of the future, assuring that barriers to new technologies are not created. Solar specific surcharges such as installed capacity fees are discriminatory, generally unsupported by facts, and impede distributed solar generation system economics. [1] The Criteria and Principles herein do not distinguish between regulated and restructured states. However, rate designs, cost allocation methods, avoided costs and cost/benefit analyses must recognize whether the utility is distribution-only or vertically integrated. Download a copy of the PDF here.                        

What Home Owners Need To Know About Battery Storage Systems

Since the sun does not shine at night we need a way to store daytime-generated solar energy. Net metering is an elegant and 100% efficient way to shift excess solar power, but that system will not work at high solar penetration levels. Never mind the fact that utilities are loath to allow their customers to generate electricity for less than it costs them to deliver this power. 

As a result, battery storage is on the minds of almost all new solar customers. Storage technology, incentives, favorable electric rates and control software are all evolving rapidly. There are currently about a dozen companies with battery storage systems designed for use with rooftop solar. Like peanut butter and chocolate, many solar companies are starting to offer battery storage systems along with their solar systems.

My advice is to proceed with caution. Even though off-grid battery storage systems have been available for years, we are at the very early stages of grid-tied solar combined with battery storage. From a hardware standpoint, battery storage costs are plummeting, and new inverters/charge controllers are being developed. Perhaps more importantly, software that will efficiently interact with solar, batteries, the grid and your home energy consumption still has limited functionality. For more about the practicalities of home battery storage, Listen Up to this week’s Energy Show on Renewable Energy World.

Barry Cinnamon http://www.renewableenergyworld.com/articles/2017/05/what-home-owners-need-to-know-about-battery-storage-systems.html

Arizona utility signs game-changing deal cutting solar power prices in half

Arizona solar array. CREDIT: Tucson Electric Power.

Tucson Electric Power to buy new solar power at under 3 cents per kWh, a “historically low price.”

Remarkable drops in the cost of solar and wind power have effectively turned the global power market upside down in recent years.

We’ve seen prices for new solar farms below 3 cents per kilowatt hour (kwh) in other countries for over a year now, but before this week, not in the U.S. That changed on Monday when Tucson Electric Power (TEP), an Arizona utility company, announced that it had reached an agreement to buy solar power at the same game-changing price.

TEP says that this is a “historically low price” for a 100-megawatt system capable of powering 21,000 homes — and that the sub-3-cents price is “less than half as much as it agreed to pay under similar contracts in recent years.”

For context, the average U.S. residential price for electricity is nearly 13 cents per kwh, and the average commercial price is 10.5 cents.

NextEra Energy Resources will build and operate the system, which also includes “a long duration battery storage system” (whose price is not included in the 3 cents/kwh). Also worth noting: The sub-3-cents contracts that have been signed in other countries such as Chile, Dubai, and Mexico are unsubsidized, whereas U.S. prices include the 30 percent Investment Tax Credit.

PV Magazine reports “this is the lowest price” they’ve seen for solar yet in this country. And Bloomberg New Energy Finance chair Michael Liebreich explained last month that thanks to recent price drops, “unsubsidized wind and solar can provide the lowest cost new electrical power in an increasing number of countries, even in the developing world — sometimes by a factor of two.”

The TEP contract is one more sign that the renewable revolution is unstoppable.

Source: https://thinkprogress.org/arizona-utility-game-changing-solar-deal-8e7c0bcb093a


  • Welcome to the Arizona Solar Center

     This is your source for solar and renewable energy information in Arizona. Explore various technologies, including photovoltaics, solar water heating, solar architecture, solar cooking and wind power. Keep up to date on the latest industry news. Follow relevant lectures, expositions and tours. Whether you are a homeowner looking to become more energy efficient, a student learning the science behind the technologies or an industry professional, you will find valuable information here.
  • About The Arizona Solar Center

    About The Arizona Solar Center Arizona Solar Center Mission- The mission of the Arizona Solar Center is to enhance the utilization of renewable energy, educate Arizona's residents on solar technology developments, support commerce and industry in the development of solar and other sustainable technologies and coordinate these efforts throughout the state of Arizona. About the Arizona Solar Center- The Arizona Solar Center (AzSC) provides a broad-based understanding of solar energy, especially as it pertains to Arizona. Registered Read More
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