Archive for June, 2009

LEED versus Energy Code

June 30, 2009

090630 LEED certified building performance v energy code min

The US Green Building Council (USGBC) has a building rating system which measures “green” parameters, meant to be used in the design of new and renovated buildings. LEED ratings can be assigned to buildings, ranging from Certified to Platinum.

I have suspected that many of the resulting projects were energy inefficient because of the rote design methods encouraged by USGBC to achieve their ratings, antithetical to mechanical and electrical engineering . Unknowingly USGBC have tested this premise. In the graph are the results of a sampling of certified buildings USGBC examined.

21% of the buildings tested were not able to meet the efficiency minimums established by their respective governing energy codes. Amongst the buildings that failed were LEED Platinum-rated structures.

Energy Independence

June 26, 2009

refinery fire2

Cap and Trade legislation is slated for a vote. US refiners may be hard hit, so multinationals such as ExxonMobil, Valero and ConocoPhillips may end up shutting domestic refining and importing gasoline with tankers. It may be posturing, I don’t know the economics, but it would seem to discourage development of cleaner domestic refining.

Today’s WSJ reports that LNG imports are to increase, because the cost of production/shipping/regasification for LNG is about $2./MCF (for Exxon), much less than the current cost of natural gas at Henry Hub.

These developments put energy independence at risk, it would seem.

The C&T bill includes a provision prohibiting over the counter trading of emission credits. This would prohibit companies from entering into direct agreements with one another, and would require trading of credits only through a commodity exchange such as the CME.

Both sides agree that higher electric bills will result, disagreeing only on the rate of increase.

Generation Links

June 24, 2009


FPL is projecting US $7.0 Billion in fuel savings by 2014, by moving some of their generation from oil to combined-cycle, which they rate 30% more efficient. FPL claims their customers pay the lowest rates of all of Florida’s  electric utilities. Not mentioned in the press release: the PSC has granted  a 30% rate increase to Florida Power and Light, FPL’s regulated subsidiary.

The NRC will make a decision on the relicensing of Entergy’s 40-year old licenses for Indian Point sometime after next February.

Long Island has amongst the highest electric rates in the US due to a lack of generation. The Long Island Shoreham nuclear facility was licensed but never commissioned because of local pressure regarding an evacuation plan for residents. NYS inherited the nuclear facility when the utility was forced into bankruptcy.

NYS’ LIPA are trying to develop the Shoreham property. Yesterday was the deadline for RFP submissions from private real estate developers. It is not great timing for NYS, and in turn the rate payers, as they sell land into a soft real estate market.

FERC staff have studied the cost of new generation. Note the marked increase in the capital cost of nuclear.


Photo of Shoreham.

Transmission Links

June 21, 2009


Con Edison plans to spend US$1.5 Billion on infrastructural improvements in NYC and Westchester County by laying 2000 miles of cable. Their news release makes reference to the fact that the improvements are being made despite the credit crisis, but of course the ROI is guaranteed by the NYS PSC.

On June 18 Central Hudson announced they too would be improving their infrastructure, with a rate increase as granted by the NYS PSC.

Orange and Rockland (Con Edison), with a service territory covering two NYS counties, NJ, and Pennsylvania, also has transmission issues. Starting June 1, their business customers with peak demands less than 100 kW may be eligible to receive 70% of the installed cost of energy efficient lighting measures directly from O&R.

In the golden state, the governator’s Energy Plan hinges on new transmission to bring renewable energy from sources in the desert and the Tehachapis to urban centers. Here is the NOVA video file.

FERC are concerned. June 18 they released a study asking for a 38 GW to 188 GW demand reduction nationwide, or 20% of demand. As T. Boone Pickens might say, ” That’s a lot of juice.”

Energy and Emissions

June 18, 2009


Crude oil storage is high but decreasing

oil supplyGas demand is increasing

gas demandWhich leads to higher prices for regular gasoline

gas prices

The Conoco Phillips CEO  discusses emission credit assignment for refiners as compared to electric utilities in Cap and Trade legislation. This is an eight-minute interview with Fox News.

DOE has selected the four companies to receive the first US $18.5 B federal loan guarantees to construct new nuclear generation. One of the four, Unistar, is a partnership of Constellation Energy and a French electric utility, EDF.

The Maldives are striving to lower emissions.

Con Ed DR Programs Offer Customer Rebates

June 16, 2009


Con Edison and the NYISO offer customers who can reduce demand various Demand Response (DR) programs leading to rebates. Customers in New York City and Westchester County qualify. Permanent demand reductions such as lighting retrofits qualify for the Con Ed DR rebates.

Installed Capacity Program

The Installed Capacity Program (ICAP) may be activated by the NYISO in response to power shortages or other emergencies. Con Ed will contact program participants with a request to curtail their power use.

When the NYSIO anticipates that reliability of major transmission and distribution systems may be compromised, or that power demand may exceed available supply, the NYISO may declare an emergency. Con Ed will then contact program participants with a request to curtail demand under ICAP. Customers will receive an advisory day-ahead notice followed by a notice two hours before the event to curtail power.

A customer who is capable of reducing at least 100 kW of electric load for at least four hours through on-site generation or curtailed load can participate in ICAP. The two curtailment capability periods are from May 1 through October 31 and from November 1 through April 30.

Customers must have an interval meter. The meter measures and records electrical use each hour; the data are used to verify load reduction and calculate appropriate payment.  Con Edison will install the meter. For assistance with Con Ed meter replacement, go here.

Emergency Demand Response Program

The Emergency Demand Response Program (EDRP) may be activated by the NYISO as a response to power shortages or other emergencies. Con Ed will contact program participants with a request to voluntarily curtail their power use.
Customers must have an interval meter. Incentives are available for the cost of the interval meter installations through NYSERDA’s Existing Facilities Program.

Any Con Ed customer capable of reducing at least 100 kW of load for four hours can participate in EDRP. Customers enrolled in EDRP are not eligible to participate in ICAP.

Customers will receive the greater of $.45 for each kilowatt-hour curtailed, or 90% of the price of energy in the real-time wholesale market, the real-time zonal Locational-Based Marginal Price.

Customers will also receive Con Ed’s Demand Monitoring Software, software which can be used to identify ways to reduce electricity consumption and lower operating costs.

Distribution Load Relief Program

The Distribution Load Relief Program (DLRP) is designed to temporarily reduce electricity use to help maintain reliable service on the Con Ed delivery system.

Customers must have an interval meter.

Any Con Ed customer who can reduce usage by at least 50 kW can participate in DLRP directly or through an aggregator. Customers who do not meet the minimum reduction can apply through an aggregator who will combine customer loads to participate.  Customers are required to provide load reduction for no less than four hours during an emergency event.

There are two ways to participate in DLRP. The voluntary option pays incentives for electricity not used. The mandatory option also pays for electricity not used during an event and pays a monthly incentive for a guaranteed reduction commitment. Participants in the voluntary option will receive the greater of $.50 per kWh curtailed, or the real-time zonal Locational-Based Marginal Price less the retail rate for an event.

Payments in the mandatory option are based on a tier system. Tier I payments are $3.00 per kW-month for six load events of four hours each in a designated network. Tier II payments are $6.00 per kW-month for six events of four hours in a designated network.

Additional payments for the mandatory option:

1. Additional $1.00 per kW-month for more than six events but fewer than 10 events, or more than four hours but less than eight hours per month per capability period.

2. Additional $1.50 per kW-month for ten or more events and / or if the event lasts more than eight hours per month per capability period.

Mandatory option participants who do not provide the full amount of committed load reduction during either a test or event will be expelled from the mandatory DLRP.

Photo: NYC skyline from a lower midtown rooftop during August 2003 blackout, credit John Wehr.

Electrical Links

June 12, 2009


UK company E-light is out with resonant asymmetric inductive supply (RAIS), a dimming protocol for LED which works with most dimmers, including MOSFET-based dimmers.

Sylvania has a brochure with suggested ways for municipalities to invest their Recovery Act funds.

Seoul Semiconductor introduces a 120 lumen / watt LED with precision dome lens and metal substrate.

DOE has a 1.0 megabyte PDF outlining their 2009 portfolio of R&D projects related to Solid State Lighting.

Speculation has begun regarding lighting power density and lighting control requirements in ASHRAE 90.1-2010.

On June 2 electrical engineers representing the IEEE in Piscataway and NATO in Brussels agreed to develop common standards for human exposure to electromagnetic fields.

Lighting and Wind

June 10, 2009



In the May 13 post, reference was made to NYSERDA Existing Building Program providing funding for lighting upgrades. This is on a per kWh saved per year, a one-time payment. The rebate for Orange and Rockland (Con Edison) customers is $0.12/kWh saved/year, for the first year only.

In response to my question, yesterday the agency ConEd PM clarified the links for the spreadsheets required for the calculations:

“A description of our electric incentive program is here:

“You can download the lighting form by clicking on the link under the “lighting” bullet point.


Go here for assistance with calculations.


It is reported today that climate change is having a negative impact on midwest US wind speeds of as much as 10%, negative in relation to wind generation potential.


The photo at the top is taken near shore off Maui. There are 12 GE 2.0 MW turbines on the ridge. Can you spot them? No Photoshop was used, it’s our photo.

Maybe turbines can enhance the landscape, depending on the skills of the design team.

An LED Driver Design for High Currents

June 9, 2009

blockHigh-brightness LEDs are being used in luminaires for commercial downlighting, and industrial, architectural, exterior, and emergency lighting.

To produce more lumens, some LED designs require forward currents to increase. Typical LED forward currents range from 350 mA to 1000 mA; a few of the latest LED require up to 3000 mA.

To address this high current approaching 3 Amps, some driver solutions are utilizing innovative switching.

The majority of LED driver solutions available are based on standard voltage-regulator, using a fixed frequency, current-mode-control buck converter. Control schemes tend to be complex, often having two loops: an outer-loop to regulate the current control and an inner-loop to provide the peak current control. This control technique typically requires external compensation components.

Brightness control is difficult to achieve. Most solutions rely on pulse width modulation frequencies in excess of 200 Hz to avoid flicker. A good dynamic range for brightness control requires the ability to modulate to duty cycles as low as 10%. With a 200 Hz signal, this means the driver has to support the ability to turn on and off in a period of 0.1 × 1/200 seconds = 0.5 ms. As some driver solutions have a soft-start feature in the region of several ms, this can restrict the dynamic control range.

The voltage in the current-control loop can be as high as 1.2 V, which has a large impact on the power dissipation. When driving a single LED with a forward voltage (Vf) of 3.5V, the efficiency drops by 34%, even before other losses are considered.

The diagram shows a circuit built around a driver designed for driving high-current LEDs. With a simplified control scheme, the component count includes two resistors, two capacitors, one Schottky diode, and the power inductor (L). An output capacitor is not required because the peak-to-peak current ripple can be as low as 10% of the maximum LED current. This meets the majority of high bay LED lighting applications.

The design uses an inner-loop that controls the current by sensing the voltage developed across the sense resistor (R2) during the recirculation diode (D) conduction phase. No outerloop is required, removing the need for external compensation components.

Soft-start is not used in the design, so expect the life expectancy of the driver will be less than drivers that do provide soft-start, and as such the driver design is best deployed in applications not requiring repeated starting or on-off switching.

Portions excerpted from a whitepaper by Peter Tod

Initiatives from Con Edison

June 5, 2009


Con Edison is testing fault current interrupters from British company Zenergy. The device uses a superconductor to reverse the current when it senses a current overload.

Con Ed has joined LIPA in an initiative to construct a wind farm off the Rockaways. The first phase of their study concluded that with improvements to their respective transmission systems, an interconnection of up to 700 MW is feasible.

Digital relief map courtesy Karen Mulcahy.