I utilize geothermal heat pumps, solar thermal, and photovoltaics in many of my projects globally. And my home in Arlington, Virginia has a direct-exhange (no ducts) geothermal heat pump, solar water heater, and a 4.7 kW PV system with a batty bank. The geothermal makes the house a zero energy building because of the energy load reduction, primarily for cooling. These three technologies are economic and work well together. Scott Sklar, President, The Stella Group, Ltd.
Geothermal using ponds is much more energy intensive than almost all of the modern closed-loop geothermal systems. I also use in my home a refrigerant-based geothermal heat pump system which cut drilling cost by 75% and has been working great. So overall, geothermal technologies in proven, commercial systems, is cost effective. Scott Sklar, Adjunct Prof, GWU
This article is not accurate. For the last 14 years, my company has been brought on by commercial, industrial, and military clients to blend pv, small wind, micro-CHP, micro-hydropower to charge battery banks for dedicated electric loads. These systems void the need for diesel back-up generators (including the monthly costs for testing, O&M, and 18 month trade-lit of diesel fuel). They also obviate the need for power quality equipment such as surge protectors (which also need replacement due to surges, sags and transients which ruin digital equipment). They also offset uniquely high electricity sub rates expressed as demand charges, peak & seasonal rates, and spot or ratchet rates). When these three costs are voided, batteries are quite cost effective. My home in Arlington VA has a PV battery system, as does my small office which has PV roofing shingles and a small wind turbine. These residential and small business systems are economic in a fourth of the USA with high electricity rates including Hawaii, Long Island (NY), etc. Scott Sklar, President, The Stella Group, Ltd. (email@example.com)
I am sorry, but a few hundred birds from a concentrated solar power plant - we have 15 now and maybe will have 150 - or 4,500 to 45,000. On January 30, 2013 released, "Cats that live in the wild or indoor pets allowed to roam outdoors kill as many 3.7 billion birds in the continental U.S. each year", says a new study published in Nature Communications. The Washington Post published a study's findings on Feb 3, 2014 that up to 988 million birds collide with windows and die. The biggest share comes not from skyscrapers but from crashes into smaller buildings. And on Nov 26, 2011 an NBC News report quoted that "tens of millions of flamingos, storks, pelicans and other migratory birds are being killed each year when they fly into power lines", according to a new international study. Let's focus on the billions, hundred of millions, and tens of millions before singling out a few thousand. Scott Sklar, Adjunct Professor, GWU
A great article, but readers should know that MIT's geothermal study showed that the US could conservatively meet 10% of our electricity needs from geothermal - a 24 hour zero emissions energy source. Geothermal is an essential tool to get the US electric grid to net-zero emissions, and requires the entire portfolio of high-value energy efficiency and renewable energy options. We have immense geothermal potential in the western US, and the MIT report says the Appalachian region also has a significant resource. Time for federal and State tax policies, environmental and utility regulatory policies, and local permit and land use policies to drive the maximization of our geothermal resource. - Scott Sklar, Adjunct Professor, The George Washington University and Steering Committee Chair, Sustainable Energy Coalition (Washington, DC)
Energy storage at the customer-side of the meter is on an upswing, where solar (small wind, microCHP systems, etc) are charging battery banks dedicated to critical loads in buildings and infrastructure. As electric utilities start to put up barriers like standby charged, most of my company's commercial projects employ 'smart' battery banks to isolate critical loads that need absolutely reliable power and clean power (no surges , sages, and transients that harm digital equipment). The California mandate of 2.5 GW and the PJM ISO on the east coast are pushing systems for frequency regulation, which will drive larger battery systems along power lines interacting routinely with the electric grid. This will bring down battery costs further and build the learning curve. Battery materials are in a materials science renaissance, where costs will drop and new attributes tied to longer life are now oozing into the marketplace. The data that batteries are not cost effective is really silly, because if you store lower cost electricity for the times of higher costs electricity, alleviate the need for diesel back-up systems ( and their ongoing testing, O&M and diesel fuel change-out costs) and drop the need for power quality equipment and ongoing replacement (for surge, sag and transient protection) -- in many cases battery storage systems are cost-effective and viable now. - Scott Sklar, Adjunct Professor, GWU, and President, The Stella Group, Ltd. (Washington, DC)
Some general observations on the article and some of the comments. Net metering generally applies to solar, but can also apply to on-site wind energy, too. Net metering generally is a benefit to electric utilities but energy efficiency and consumer-based renewables are fundamentally hurting the electric utility industry's bottom line, and a great article is on the front page of today's Wall Street Journal (7\29\14) "Electric Utilities Get No Jolt". Battery storage is increasingly becoming an answer on both sides of the electric meter. For electric utilities, batteries and other types of storage, provide frequency control and acts like a "spinning reserve". For consumers, it allows them to isolate from the electric grid (thus avoid standby charges), or shed loads during higher cost sub rates (expressed as demand charges, peak and seasonal power rates, as well as 'spot' market or ratchet rates). Net metering should be preserved along with energy efficiency incentives, new requirements for energy storage such as the 2.5 GW mandate by the State of California.
Russell is right on target with this article. And two electric bus manufacturers in the US have been pushing this very idea. Electric utilities have thud ands of diesel generators along transmission ones used for line voltage augmentation to prevent is landing. These buses, when not in use, can be parked along lines to do that, and then take their charge before they need to do a school run. The buses can be used during emergencies as mobil on-site power providers for first responders, or for critical functions - cell towers, pipeline pumps, etc. V2G is a viable tactic for resiliency and we need to take this approach more seriously. Thanks for writing this article. - Scott Sklar, Adjunct Professor at The George Washington University
I want to commend the author for not promoting pesticide-intense solutions for controlling vegetation growth under PV arrays. The use of animals, such as emus and goats, as well as certain sheeting and cloths are more optimum and low-energy ways to achieve the same result. We don't want to create other problems such as groundwater contamination, etc. and health impacts of introducing hormone disruptors and immune suppressors into the environment. Great article. Scott Sklar, Adjunct Prof, GWU
There is no one battery technology that is perfect. And while the costs and size issues in the article are correct for this moment, they will change dramatically over the next decade -- and there are several other types of commercial batteries available beyond the two mentioned. Liquid electrolytes are great in a controlled area, but not so in remote or mobile applications (or hard-to-reach sites). Scott Sklar, Adjunct Prof, GWU and President, The Stella Group, Ltd.
There are many omissions in the UN study from many viewpoints. While micro grids are one important omission, I disagree with the author's view that distributed generation is not an equal path -- indeed it is essential, particularly for low-power and critical infrastructure. Dedicated distributed generation (DG), not linked and thus not susceptible to cybersecurity problems, is also an essential tool. There is no one path or approach .. the more parallel approaches and redundancies are the principles that are required.