El proyecto en la isla de Bornholm utilizará las baterías de los coches aparcados para almacenar el exceso de energía cuando el viento sopla fuerte, y devolver de nuevo la electricidad a la red cuando el tiempo está en calma.
El concepto, conocido como del vehículo a la red (vehicle-to-grid o V2G) es ampliamente citado como un paso clave hacia un futuro descarbonizado, pero nunca se ha demostrado. Ahora, los 40.000 habitantes de Bornholm están siendo reclutados para el experimento. Dinamarca ya es un líder mundial en energía eólica y tiene planes para reemplazar el 10% de todos sus vehículos por coches eléctricos, pero el objetivo en la isla es sustituir todos los coches de gasolina.
Actualmente el 20% de la electricidad de la isla proviene de la energía eólica, a pesar de que ha instalado suficientes aerogeneradores para satisfacer el 40% de sus necesidades. La razón por la que no puede utilizar toda la capacidad es la intermitencia del viento: se necesitan muchos aerogeneradores para producir suficiente electricidad con las brisas, pero cuando el viento sopla fuerte la red se sobrecarga, por lo que algunos aerogeneradores se desconectan.
Por lo tanto, el objetivo del proyecto denominado "Proyecto de vehículos eléctricos en un mercado integrado y distribuido basado en energías sostenibles y redes abiertas", cuyo acrónimo en inglés es Edison, es utilizar la V2G para permitir incrementar la aportación de la eólica y ofrecer hasta un 50% de la electricidad de la isla a partir de energía eólica sin afectar a la red.
Cada vehículo eléctrico tendrá reservada una parte de la capacidad de la batería para almacenar energía eólica generada en la isla y no para de viajar. Esto significa que actúan como un amortiguador, dice Dieter Gantenbein, investigador del IBM Zurich Research Laboratory. IBM está desarrollando el software necesario para la red inteligente de la isla, y mostrará su trabajo la próxima semana.
Cuando los coches están conectados y recargando sus baterías, lo hacen con la electricidad que la red no puede absorber y posteriormente la devuelven cuando se necesita para el consumo de las viviendas.
"Nunca se había hecho en esta escala", dice Hermione Crease de Sentec, con base en Cambridge, que desarrolla el software para la red inteligente. Hay un montón de ensayos de redes inteligentes ya en marcha, que por lo general implican el uso de software para supervisar y gestionar la oferta y la demanda de electricidad como, por ejemplo, apagar temporalmente las unidades de refrigeración industrial durante los periodos de máxima demanda. Pero, a diferencia de los llamados enfoques fundados en los "negavatios", aún no se había intentado probar que los coches pueden utilizarse como parte de la red eléctrica.
Andrew Howe, de RLTec con sede en Londres, otra empresa de tecnologías de redes inteligentes, señala que muchas preguntas importantes necesitan respuestas. No está claro, por ejemplo, cómo el coste y la duración de las baterías influirán en la economía de dicho sistema.
Este es el tipo de cuestiones sobre las que el proyecto intenta arrojar luz, dice el director del proyecto Jørgen Christensen, de la Asociación Danesa de Energía, que junto a las empresas Siemens y Dong y el Gobierno están ejecutando el plan.
Denmark to power electric cars by wind in vehicle-to-grid experiment
The project will use electric car batteries to store excess energy and feed electricity back into the grid when the weather is calm
Cars could be the solution to the intermittent nature of wind power if a multimillion European project beginning on a Danish island proves successful.
The project on the holiday island of Bornholm will use the batteries of parked electric cars to store excess energy when the wind blows hard, and then feed electricity back into the grid when the weather is calm.
The concept, known as vehicle-to-grid (V2G) is widely cited among greens as a key step towards a low-carbon future, but has never been demonstrated. Now, the 40,000 inhabitants of Bornholm are being recruited into the experiment. Denmark is already a world leader in wind energy and has schemes to replace 10% of all its vehicles with electric cars, but the goal on the island is to replace all petrol cars.
Currently 20% of the island’s electricity comes from wind, even though it has enough turbines installed to meet 40% of its needs. The reason it cannot use the entire capacity is the intermittency of the wind: many turbines are needed to harness sufficient power in breezes, but when gales blow the grid would overload, so some turbines are disconnected.
So the aim of the awkwardly named Electric Vehicles in a Distributed and Integrated Market using Sustainable Energy and Open Networks Project – Edison for short – is to use V2G to allow more turbines to be built and provide up to 50% of the island’s supply without making the grid crash.
Each electric vehicle will have battery capacity reserved to store wind power for the island rather than for travelling. This means it acts like a buffer, says Dieter Gantenbein, a researcher at IBM’s Zurich Research Laboratory. IBM is developing the software needed for the island’s smart grid, and will showcase its work next week. When the cars are plugged in and charging their batteries, they will absorb any additional load the grid cannot cope with and then feed it back to power homes when needed, he says.
"It’s never been tried at this scale," says Hermione Crease of Cambridge-based Sentec, which develops smart grid software. There are plenty of smart grid trials already under way, usually involving the use of software to monitor and manage supply and demand, for example, by temporarily switching off industrial cooling units during periods of peak load, she says. But unlike these so-called "negawatt" approaches, proving that cars can be used as part of the grid has yet to attempted.
Andrew Howe of RLTec in London, another smart grid technology firm, says many important questions need answers. It is not clear, for example, how the cost and lifetime of batteries will influence the economics of such a system.
These are the kinds of issue the project seeks to shed light on, says the project manager Jørgen Christensen of the Danish Energy Association, which with technology companies Siemens and Dong and the government are running the scheme.
Google Developing Smart Charging for Plug-In Electric Vehicles
You didn’t think Google would end its involvement in the smart grid industry with PowerMeter, did you? The Internet giant announced yesterday that it’s working on smart car charging software–the place where IT and ET (energy technology) meet, according to Google.org’s Dan Reicher.
The software, which is still in the prototype stage, will tackle the future issue of millions of plug-in hybrid electric vehicles (PHEVs) charging at the same time and straining the electrical grid. Google’s software will use so-called vehicle dispatch algorithms to smooth the load on the grid, optimize use of on-the-grid solar and wind power, and generally make things easier for grid operators by helping to maintain a steady frequency on transmission wires. This steady frequency should reduce the need for utilities to increase or decrease electricity flow to keep pace with demand.
Vehicle-to-grid technology–a system where EV batteries feed captured electricity to the electrical grid when necessary–is still years away. Google’s one-way grid-to-car system, in contrast, could hit the streets much sooner. Of course, Google isn’t the only company working on smart charging software. The Chevy Volt will have a smart charging system when it’s released next year, and Pacific Northwest National Laboratory announced in April the development of its own smart charger controller.
Electric cars seen as killer app for smart grid
Where you see an electric car, your utility sees a battery on wheels.
Forward-looking utilities are gearing up to tap into the stored energy that plug-in electric vehicles can provide using smart-grid technology, said industry executives at consulting firm Kema’s Utility of the Future conference here this week.
Car batteries can provide a buffer to lighten the load on the grid during peak times and potentially provide back-up power to homeowners. Down the line, old plug-in hybrid electric vehicle (PHEV) batteries could be recycled as storage devices, they said.
"I think PHEVs will be the killer application for the smart grid," said David Mohler, the chief technology officer of Duke Energy. "They are able to both consume and provide energy like no other device can and can really change storage."
A number of plug-in electric vehicles aimed at mainstream buyers will become available over the next two years. Although there’s no standard storage capacity, Mohler estimated that four of them could power a house, at least for a short time.
In the near term, the most promising marriage of the grid and car batteries is providing what the power industry calls "frequency regulation." It’s an arrangement that could save utilities money, reduce pollution, and potentially save consumers money, advocates of the approach said.
Utilities routinely pay for frequency regulation services to ensure that the supply of electricity matches the demand. When an imbalance between supply and demand causes a change in signal frequency, power generators crank up to adjust the flow of electricity.
But a network of plugged-in electric vehicles could effectively perform the same function by taking a break–even for a few minutes–from charging their batteries. Charging cars in bursts–all while ensuring they’re topped off when the drivers needs them–could be done with millions of cars, said Alec Brooks, a renewable energy engineer at Google.
Google has developed proof-of-concept "smart charging" software with algorithms that monitor the electricity supply and very precisely control when cars get charged, he said during a presentation where he showed simulation data. "You figure out which ones you need to dispatch (electricity) to be full when they say they need to be full," Brooks said.
Using car batteries for frequency regulation–already a billion-dollar market–is more cost-effective and would allow power generators to take better advantage of wind and solar power, which are variable, Brooks said. Google is testing the software on its fleet of eight converted plug-in hybrid Priuses.
"You can shape the load to match renewable energy, which can be very different even within one day…So you have a system where you move the load around rather than the generation," he explained.
Saving money on the Chevy Volt
It’s not just software engineers at Google who are tooling around with PHEVs and frequency regulation. When the Chevy Volt is released at the end of next year, the car will have smart charging built into it using the OnStar service.
In a Department of Energy research project, General Motors is working with 50 utilities to see how the Chevy Volt can interface with utilities. Providing grid services, such as frequency regulation, will lower the cost of owning the Volt, said Keith Cole, GM’s director of advanced vehicle strategies and legislative affairs.
"If a customer can sign up and say they are willing to have their charging interrupted for 140 seconds and the utility will pay them to do it via a credit, it would cut the cost of charging the Volt," Cole said. "So instead of costing 7 or 10 cents a kilowatt-hour, it might cost 5 or 3 because of the service."
Although this will be technically possible when the Volt is first released, don’t expect it to be available for a while. The business models for these types of services have yet to be worked out.
Still, cutting electricity demand for frequency regulation makes sense for utilities because the power purchased for this job is relatively expensive, Cole said, adding that a utility would only be interested if it could get large numbers of cars under management.
Farther out, utilities could potentially pull stored electricity in car batteries to lighten the load on the grid, rather than fire up an expensive and dirty auxiliary power plant during peak times. But that two-way power flow, called vehicle-to-grid, is technically challenging and puts added strain on the battery.
To illustrate how the auto and electricity industries are connecting, Chrysler anticipates that it will be producing over 1 gigawatt of electrical capacity per year by about 2015, said Tom Sacoman, the portfolio executive of Chrysler’s ENVI electric auto division. That’s about as much power as a nuclear or coal plant can produce.
Sacoman anticipates that customers will be offered a range of options–sort of like cell phone pricing plans–when they buy an electric car. In some cases, they would allow the utility to control the speed of battery charging in exchange for a discount. In other plans, the customer would not cede control at all and pay full tariff.
Although it’s still years away, utility companies already have designs on used-up plug-in electric vehicles’ storage, most of which will be lithium ion batteries. The Chevy Volt’s battery life, for example, will have a 10-year, 150,000-mile warranty.
But some grid energy storage executives think customers will swap out a car’s original batteries for newer, better ones sooner than that as the performance degrades. Those same batteries could be recycled, either to provide back-up power in a home with solar panels, for example, or looped together as big storage banks for utilities.
"A battery could be taken out of that car and used for a stationary application in a home where it could live for many years," said Brad Roberts, chairman of the Energy Storage Association. "But who owns the battery? To make PHEVs really take off, we need to have consumers buy the car and lease the battery."
Battery leasing is essentially the business model developed by BetterPlace, which owns car batteries and provides charging stations at homes and public places. Having cars plugged in as often as possible makes grid services, such as frequency regulation, far more feasible, executives said.
Just like getting discounts for consumers offering grid services with their electric cars, recycling old electric batteries for storage needs a viable business model. Some entity will need to collect them and repackage them for utilities, said Ali Nourai, manager of distributed energy resources at utility AEP.
"We know the auto industry will bring the prices down for batteries," Nourai said, who estimated it would take about 10 years before these car batteries will be available. "We don’t need a brand new battery."
The EDISON project – Electric vehicles in a Distributed and Integrated market using Sustainable energy and Open Networks
Periode: 2009 to 2012
• Danish Energy Association
• CET, DTU Electrical Engineering
• DTU Informatics – IMM
• Dong Energy
• RISØ DTU
Projektleder: Afdelingschef Jørgen S. Christensen, Dansk Energi
Electric vehicles (EVs) provide a unique opportunity to reduce the CO2 emissions from the transport sector. At the same time, EVs have the potential to play a major role in an economic and reliable operation of an electricity system with a high penetration of renewable energy.
EVs will be a very important balancing measure to enable the Danish government’s energy strategy, which implies 50% wind power penetration in the electric power system. An EV will be a storage device for smoothing power fluctuations from renewable resources especially wind power and provide valuable system services for a reliable power system operation.
With the proper technology the cars can run on wind power and at the same time enable an increased share of RES in the power system for supply of the conventional electricity demand, and thereby, provide an overall economic, reliable, and sustainable energy system.
Denmark does not have a car industry, and the Danish background for development of EVs themselves is limited. On the other hand Danish companies and research institutions have a very strong knowledge and competence regarding design, development, and operation of power systems with high penetration of distributed generation.
Furthermore, Danish industry is involved in technologies, which are critical to a widespread use of EVs such as strategy for optimised battery charging/discharging, and power electronics related to battery charging/discharging. This forms an ideal base for development of systems and integration solutions for EVs.
The Danish competence can be utilised to develop optimal system solutions for EV system integration, including network issues, market solutions, and optimal interaction between different energy technologies. Furthermore, the Danish electric power system provides an optimal platform for demonstration of the developed solutions, and thereby, provides the commercial basis for Danish technology export.
Furthermore, the advantage of being a “first mover” constitutes a business advantage, as well as, a possibility of a strong Danish influence on future standards for system integration of EVs, whereby optimal utilization of the EVs in the power system is obtained.