Category Archives: Distributed Generation

New NREL Study:
 Prodigious Potential
 For Rooftop PV In U.S.

Distributed Generation, Environment, Forecasts, Solar, ,

It’s pie-in-the-sky by design, but a new report from DOE’s National Renewable Energy Laboratory on the technical potential of rooftop solar in the U.S. is eye-opening nonetheless. All told, NREL said, some 1,118 gigawatts (GW) of capacity could be installed if all the “suitable” rooftops in the U.S. were covered with PV panels, generating upward of 1,432 terawatt-hours (TWh) of electricity annually—roughly 39 percent of total annual electric sales.

NREL is quick to point out that the study, Rooftop Solar Photovoltaic Potential In The United States (which can be found here), did not look at economics. As such, the study represents “an upper bound on potential deployment rather than a prediction of actual deployment.” But even on this basis, the study found that solar’s potential has expanded significantly in the past decade: A similar study on solar PV’s technical potential that NREL completed in 2008 estimated that 664 GW of rooftop capacity could be installed, generating roughly 880 TWh of electricity annually. The difference between the two estimates, NREL wrote, “can be attributed to increases in module power density, improved estimation of building suitability, higher estimates of the total number of buildings, and improvements in PV performance simulation tools that previously tended to underestimate production.”

Taking that statement at face value, it is almost certain that PV’s technical potential is going to continue rising in the years to come. In particular, NREL noted that its analysis is based on an assumed module efficiency of 16 percent; a figure it used to better represent a mixture of installed systems, not just premium PV panels. If the analysis had assumed a module efficiency of 20 percent, which is where premium systems are today, “each of the technical potential estimates would increase by about 25 percent above the values stated in this report,” NREL wrote.

Continue reading New NREL Study:
 Prodigious Potential
 For Rooftop PV In U.S. →

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Taking A Step Back
 Brings Energy Revolution
 Clearly Into Focus

Department of Energy, Distributed Generation, Environment, Forecasts, Solar, Uncategorized, Wind, ,

It is easy to get lost in the day-to-day minutia of the revolution under way in the energy industry—announcements of technology improvements, installation milestones and price reductions of all kinds hit my inbox almost daily. But two recent reports, one highlighting where we’ve been and the second pointing to where we are going, are a useful grounding tool, pointing out that while I (and probably many others) often get lost looking at individual trees there is a whole forest out there.

The first report, an Energy Department publication dubbed Revolution…Now (which can be found here), walks through the startling changes in five clean energy technologies during the past five-plus years. While much of this information may be familiar, it is worth a quick review.

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 Brings Energy Revolution
 Clearly Into Focus →

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LEDs Pose Same Threat
 As Solar & Net Metering
 For Utility Ratemaking

Distributed Generation, Environment, Ratemaking, Solar, Utilities, ,

What is the difference between LEDs and residential solar panels? Plenty, clearly, but for a utility executive worried about slow or no load growth they amount to exactly the same thing—trouble.

I have written extensively about the broad utility-led campaign to quash state net metering programs (see these posts here and here). In general, this effort is based on the premise that net metering unfairly benefits residential solar users (by overpaying them for their generation) and shifts costs onto non-solar customers (by forcing companies to charge them for the fixed costs no longer being paid for by the solar customers through their electricity purchases). But that premise is also true of LEDs if you think it through.

This week I decided to replace a bank of six aging incandescent lightbulbs in my home’s master bathroom with new LEDs—something homeowners are doing with increasing frequency around the country. In years past, this would have been a non-event, but with LEDs’ vastly improved efficiency and lengthy lifespan the equation has changed significantly.

I did a little back of the envelope calculating about the switch: The six bulbs I pulled out consumed 260 watts of electricity when turned on (for reasons unclear to me I had five 40W bulbs and one 60W bulb installed in the bathroom), the new ones just 66W total (and they are brighter to boot, but that is another story). So, every time I turn on the bathroom light switch I am saving 194 watts. That’s an admittedly small amount of power, but if you figure the lights are on for three hours daily that adds up to 582 watt-hours per day. That’s still not much, but over the course of a month, these six lights could save me on the order of 17.5 kilowatt-hours (30×582=17,460 watt-hours or 17.46 kwh).

Continue reading LEDs Pose Same Threat
 As Solar & Net Metering
 For Utility Ratemaking →

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Reliability Is Key Issue
 For Electric Utilities
 In Changing Market

Distributed Generation, Utilities, ,

 It’s not always about dollars and cents.

In a recent article in Utility Dive (the full piece can be found here), Tucson Electric Power’s Carmine Tilghman made a big deal about the unfavorable economics of Tesla’s current 7 kilowatt-hour Powerwall battery option, which he said would cost consumers $7,000 installed. As quoted by Utility Dive, Tilghman said: “At the average all-in electricity rate of $0.12 per kwh, the buyer saves $0.84 per day. And $7,000 divided by $0.84 per day means it will take 8,333 days or about 22.9 years to get the initial investment back for a battery that comes with a ten year warranty.”

Regardless of whether Tesla’s Powerwall actually ends up costing $7,000 installed, utility executives are kidding themselves if they think it is only about dollars and cents. Economics are important, to be sure, but reliability is, as a popular current commercial concludes, priceless.

tesla-powerwall-battery-specs-01.jpg.650x0_q70_crop-smart

Just this week I would have paid just about anything to have had Tesla’s battery backup (or anybody else’s for that matter) installed on the wall in my garage. Construction on a new house two down from mine necessitated the installation of a new power transformer on our street. Dominion, my provider, duly showed up, knocked the power off on my block for an hour and hooked up the new equipment. No harm, really, except that since I work out of my home that was 60 minutes of essentially wasted time.

Unfortunately, that was not the only time I wasted day. Later in the evening when I went to turn on the TV (I pay for a bundled internet/phone/TV package through Verizon) nothing happened. The menu info showed up at the bottom telling me that I was watching the Washington Nationals play the first of three games against the Cincinnati Reds—but there was no video, just a blank black screen.

An hour and a half later after the Verizon FIOS tech support guy had had me reboot, disconnect/reconnect, unplug and plug in every cable box in my house (This is standard fare for virtually all customer support these days—when a piece of electronics does not work you are almost always told to turn it off and then back on. For mystical reasons unclear to everyone, that often does the trick.) he finally agreed that I might actually need a real technician to come examine my problem.

Of course, since there seem to be only five of them in Verizon’s entire Washington, DC service territory, the earliest appointment was three days off—so much for watching any of the Nationals/Reds games. And even then, I have no guarantee that the problem, whatever it is, will be fixed.

However, if I had a battery backup installed at my house, none of this would have happened. Dominion would have turned off the power on my block, my battery would have kicked into operation, the power surge that apparently killed my FIOS video feed never would have occurred and I likely would not even have known that the power company was working just two houses away.

Now that truly would have been priceless.

–Dennis Wamsted

 

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Utilities Risk Losing
 Commercial Customers
 Without New Approach

Distributed Generation, Ratemaking, Solar, Utilities,

The U.S. commercial sector spent just under $146 billion on electricity in 20141, and that has prompted business leaders across the country to sit up and take notice.

In a fascinating study released late last month, Deloitte’s Center for Energy Solutions reported that 79 percent of the businesses it surveyed viewed cutting their electricity expenditures as “essential to creating and maintaining competitive advantage.” To this end, the survey (which is available here) found that 57 percent of the businesses surveyed have formal energy reduction goals—up significantly from the 46 percent that said they had such goals the year before.

This transition is occurring even though electricity prices are relatively low currently, and businesses do not expect substantial increases in the near term. In other words, energy management is quickly moving from the realm of reactive cost cutting to active planning and forward thinking: what can we do as a business to curb our energy consumption and improve our competitiveness?

The answers to that question may surprise you. Conventional measures such as sensors to raise/lower heating and cooling controls are still the go-to choice. But increasingly, Deloitte said, businesses are forging a path of their own, pushing ahead with options such as in-house batteries and onsite generation. Specifically, 39 percent reported installing some form of onsite generation (solar panels or other options) during the year, up from 31 percent in the previous year. Similarly, 26 percent said they installed batteries during the year compared to just 15 percent in 2014. In addition, 34 percent reported installing recovery equipment to capture previously lost energy used in production and other processes.

Deloitte

The moral of the story? Companies are increasingly concerned about their energy costs and looking for ways, both conventional and not so, to reduce their usage and boost their competitiveness. The question is, who is going to step up supply those needs?

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 Commercial Customers
 Without New Approach →

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