The Smart Grid by Bryan Welch

The Smart Grid

6/8/2010 5:43:31 AM

By Bryan Welch 

Tags: smart grid, smart meter, smart metering, net metering, alternative energy

Our current power grids are dumb.
They are great examples of 20^th-century technology, but they are going to get much better.

We have the technology, today, to make our power grid more sustainable, cleaner, more robust and more reliable just by replacing old-fashioned metering with "smart-metering"[1] and agreeing to pay enterprising power consumers for generating some of their own electricity.
Today, almost all our electricity is distributed from power plants through the "power grid" to users. The electricity only flows one way. The utility generates the power. The power flows through wires to homes and businesses. The homes and businesses use the power. The utility measures how much power is used, and charges the customer.

The new, smarter grid, allows every power customer to become a power generator as well as a power consumer. The consumer and the utility are "interconnected." "Smart meters" measure the power flowing both directions and compensates the customers for their contribution to the power supply.
Where "net metering" is available, utilities measure the customer's "net" usage. If you can generate some of your own electricity – with photovoltaics, wind or any other generator – the utility buys it from you and sells it to other customers nearby. When we distribute electricity across long distances, some of the power is lost in the process. About 6 percent of the power generated in the United States is lost to transmission inefficiencies.[2] If we empower individuals to produce their own power – and pay them for it – the electricity is distributed more efficiently because it doesn't have to travel as far.
The utility customer gets compensated for the power, the utility gets a new, inexpensive power source and the grid becomes more reliable and efficient.
Our old-fashioned grid is unnecessarily vulnerable to weather and incompetence. When things go wrong, homes and businesses can go without power for days or weeks. On a hot afternoon in August, 2003, a technician in Ohio forgot to re-start a computer program after a routine procedure, then maintenance problems shut down a nearby power plant and some power lines sagged into trees in Walton Hills and Parma, Ohio. Within hours, 55 million people in the U.S. and Canada were without power.[3] Every year hundreds of thousands of North Americans experience temporary power outages due to weather. Scientists in 2005 estimated that power outages cost the United States about $80 billion a year, on average.[4]

The principal method for preventing outages is to produce surplus electricity so that peak demand doesn't stress the system. That's costly, both for the utility and for the environment, unless that electricity is being generated by millions of individuals and businesses using clean, renewable energy sources. The utility can acquire that power at an attractive price, and it doesn't have to plow billions of dollars into new generation facilities.

Net metering and smart meters are spreading. Most of the United States have laws that authorize net metering and part of the grid was open to net metering in at least 35 states at the time of this writing[5]. Unfortunately, implementation of net metering and smart meters has been relatively slow. Consumer demand may accelerate the process in the near future, and consumers will probably drive new pricing negotiations with the utilities, as well.

Imagine a power grid that includes millions of individual generators – photovoltaic panels, wind turbines, big coal plants, natural gas co-generators, etc. – interconnected with smart meters, paying on a "net-metered" basis and supporting each other.  In mid-summer, when North American demand for electricity peaks, the photovoltaics are also generating more electricity. When overgrown trees interrupt the power supply from a coal plant in Ohio, a wind farm in Pennsylvania takes up some of the slack.

Photovoltaics and wind energy were pioneered by independent spirits who wanted to live "off the grid." The most negative aspect of an off-the-grid system is the necessity of storing electricity in batteries – an expensive, toxic and inefficient technology. Interconnection with the smart grid allows individuals and businesses to benefit from generating their own power without the necessity of storing it in batteries.

And our supply of electricity – whether or not we generate it ourselves – becomes more reliable and secure as the big industrial generators are supplemented by thousands – or millions – of small independent producers.
Unfortunately, so far utilities have hampered efforts to implement net metering on a large scale. Most of the United States limit the amount of power an independent generator can sell to the grid, even where net metering is available. In most places, consumers are pushing their utilities and governments to liberate the utility grid, so it can get smarter.

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[1] Declan Butler. Energy efficiency: Super savers: Meters to manage the future. NATURE: International Weekly Journal of Science. February 8, 2007. http://www.nature.com/nature/journal/v445/n7128/full/445586a.html. Sourced March 31, 2010.

[2] U.S. Energy Information Administration Office of Coal, Nuclear, Electric and Alternate Fuels. State Electricity Profiles 2008. March 2010. U.S. Department of Energy, Washington DC 20585. DOE/EIA-0348(01)/2.

[3] U.S.-Canada Power System Outage Task Force. Final Report on the August 14^, 2003 Blackout in the United States and Canada: Causes and Recommendations. Chapter 5. April 5, 2004.

[4] Allan Chen. Berkeley Lab Study Estimates $80 Billion Annual Cost of Power Interruptions. Research News/Berkeley Lab. Feb. 2, 2005. http://www.lbl.gov/Science-Articles/Archive/EETD-power-interruptions.html. Sourced March 31, 2010.

[5] U.S. Department of Energy Energy Efficiency & Renewable Energy. The Green Power Network: Green Power Markets; Net Metering Policies. http://apps3.eere.energy.gov/greenpower/markets/netmetering.shtml. Sourced April 1, 2010.

--
Scott's Contracting
scottscontracting@gmail.com
http://www.stlouisrenewableenergy.blogspot.com
http://www.stlouisrenewableenergy.com
scotty@stlouisrenewableenergy.com

Clash of Titans-Renewable Energy Control Wars

Scotty, Scotts Contracting: I hope this article will shed some insight into the US Grid system and how the Utility Companies view Alternative Energy Production from Solar, Wind and other Renewable Energy Producing Systems.

I feel that: when more Homes are producing Energy for their own personal use. It will lessen the Burden on Utility Companies- who in turn, would then be able to meet any Emergency Energy Demands. Because they are not being required to produce as much energy on an As-Needed basis and the Possibility of Large Scale Battery Back-Up Power. Or Better yet each home will become self sufficient and independent IE not connected to the Grid.

The Renewable Energy Control Wars: Clash of Titans

by Jon Previtali and Jon Guice, AltaTerra Research

Published: July 8, 2010

On June 25, we joined 500 executives at Stanford University for the 2010 Silicon Valley Energy Summit. The CEO of a large California utility company, Chris Johns of Pacific Gas and Electric (PG&E), was the first keynote speaker. His topic was PG&E's effort to roll out 10 million smart meters. At an average rate of 15,000 installations each day, the devices are the first and most important pieces of PG&E's smart grid infrastructure. All PG&E customers will have electric and gas smart meters by the end of 2012.

Johns noted near-term benefits familiar to most of us: no physical meter reading, faster identification of grid faults, and most importantly, lower peak power as residential customers are given the double-edged sword of time-of-use rates and "near-time" energy pricing data for the purpose of managing their power use more cost effectively.

But to those of us who are thinking about the future through the lens of solar power and other distributed generation (DG), PG&E's venture into the emerging smart grid space could mean much more. Smart meters could become the communications and control gateway to two major areas of progress for the solar power industry:

1) An increase in solar power yield through better system monitoring and remote inverter repair.

2) The deployment of much higher photovoltaic (PV) penetrations than are currently allowed in power distribution networks.

Demand for accurate solar power system monitoring and remote repair has been increasing since the commercial solar market shifted to a Power Purchase Agreement (PPA) model in which PV system operators are paid for energy delivered. There is clear incentive to maximize generation and minimize downtime. Solar monitoring companies such as FST, Draker Labs, Energy Recommerce (now National Semiconductor), and Deck stepped up to serve this market, and PPA company SunEdison even introduced its own monitoring system.

This demand has also encouraged module and inverter companies to make customer relationships more "sticky" by bundling monitoring systems that work with portfolios of systems made for their products. Module companies such as SunPower and Suntech offer complete system packages with bundled monitoring systems. Inverter companies, including Satcon, PV Powered (now owned by Advanced Energy), and SMA, are dedicating more development cycles to monitoring, communications, and control features. We also expect utility supervisory control and data acquisition (SCADA) companies will start to support big new utility projects such as Southern California Edison's and PG&E's massively distributed 250 megawatt (MW) PV implementations.

The second initiative—high-penetration PV—has even higher stakes for the solar industry.

Today, grid operators get nervous when as much as a few percent of peak load is met by renewable energy (RE) within a distribution area served by a substation. As a result, we see rules across the country that directly limit the size of solar power systems and the amount of peak load that can be met by RE. Hawaii's most populous island, Oahu, is a good example. The following rule is taken from the North Carolina Solar Center's DSIRE Database:

For customers of Hawaiian Electric Company (HECO), the maximum individual system capacity is 100 kW. The aggregate capacity of net-metered systems is limited to 1% of HECO's peak demand. Of this 1% limit, 40% is reserved for systems 10 kW or smaller.

Rules like this hinder the growth of the solar power industry. Oahu has an estimated 1.2 gigawatts (GW) of peak load. The above rule reduces that 1.2 GW to 7.2 MW of commercial solar power systems allowed on the island. At 40 cents per kilowatt hour (kWh), a common revenue target after incentives, the maximum number of commercial solar power systems on Oahu would generate $4.3 million per year. Unfortunately, that's about what a single supermarket makes each year.

So, what's the problem? Hawaii's electricity comes mostly from foreign oil, they're ranked among the highest in greenhouse gas (GHG) emitting states, and they pay the highest price for electricity. Meanwhile, they have a lot of sun. It seems they would want PV everywhere. The explanation: they don't think their grid can handle that much solar power.

And they may be right. PV systems produce power at variable rates based on available sunlight. They also automatically disconnect from the grid when they sense poor power quality or no grid power. There is no reason for concern when solar power fluctuation is a small percent of total power on a distribution grid. However, if it becomes too large, grid operators are responsible for compensating for dips and spikes. The problem is they can't. Conventional power plants don't ramp quickly enough, and operators don't control customer demand.

Also, when distributed generation (DG) exceeds load in a substation area, it flows through transformers onto transmission lines—a prospect that makes grid operators shudder. Unless they've been upgraded to bidirectional relay equipment, substations are not equipped to handle "reverse flow," meaning operators cannot measure or throttle power flowing onto transmission lines. And, if a transmission line fails, blackouts can occur.

This happened in Europe in 2006 when one of two redundant German transnational high-voltage lines was "idled" to allow a newly built cruise liner to pass underneath. The ship was late, night came, and two factors arose that resulted in the automatic curtailment of 10 million customers: an unusual rise in demand due to a cold snap in the south, and a common upsurge in wind power from the north. Despite debate over the root cause, the failure spawned Germany's Medium Voltage Directive, which appears to be the first large-scale mandate of grid operator communications and control over third-party DG.

The directive gives grid operators the ability to remotely disable RE systems connected at 10-110 kilovolts (kV), requires power ramping to prevent harmful surges and dips, enables RE systems to ride through grid faults when linemen are clearly not at risk, and may require that inverters provide reactive power to correct voltage problems. The directive seems chiefly intended to manage wind power. It's yet to be seen if it will be necessary for solar power management, because PV conveniently generates during times when solar power is most likely to be consumed by adjacent loads.

In the U.S., a similar communications and control requirement is under development by the California Independent System Operator (CAISO), which proposed its version several months ago for RE systems connected to California's transmission system. Some industry prognosticators believe the CAISO requirements will also be adopted by utility grid operators to manage single systems and system portfolios in the MW range. Considering the concern among operators, this seems like a reasonable prediction, especially as California approaches its limit for net-metered DG, currently set at 5% of peak demand.

The race is on for communications and control within the RE industry. At AltaTerra, we've coined the phrase Distributed Generation Communications and Control (DGC²) to describe this burgeoning area of information technology. With the addition of automated control intelligence to system monitoring, we believe DGC² will be essential for the coordination of all forms of DG with RE-supply and conventional demand forecasting, dynamic pricing, smart grid transmission and distribution components, SCADA systems, and a wide range of load-shedding smart grid devices yet to come. DGC² will be the brains that direct these new and not-so-new technologies to work together to reduce peak load, dampen RE variability, and safeguard grid operations as we blow past the current limits to RE DG.

Jon Guice is the co-founder and Managing Director of Research at AltaTerra Research.

Jon Previtali has 13 years experience in product management, specializing in renewable energy and related fields such as energy efficiency, smart grid devices and energy storage. Prior to AltaTerra, at SunEdison, the largest generator of solar power in North America, Mr. Previtali managed the operations service for third-party systems, assisted in the development of the solar power fleet monitoring system and developed a high-penetration PV-grid integration strategy. Jon Previtali also launched SunEdison's channel partner program, which has resulted in over 100 MW of solar power projects and is today responsible for the majority of SunEdison's system construction. Earlier, Mr. Previtali was the Director of Product Management for Monitoring and Reporting Services at Digital Island, a leading Internet infrastructure firm. He holds a B.S. in Civil Engineering from Stanford (1993) and an M.S. in Civil, Environmental and Architectural Engineering from the University of Colorado, Boulder (2007).

The information and views expressed in this article are those of the author and not necessarily those of RenewableEnergyWorld.com or the companies that advertise on its Web site and other publications.

-- Scott's Contracting scottscontracting@gmail.com http://www.stlouisrenewableenergy.blogspot.com http://www.stlouisrenewableenergy.com scotty@stlouisrenewableenergy.com