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Can Denmark make energy demand follow renewable supply?

September 7, 2015 at 6:25 PM EDT
By 2050, Denmark hopes to get 100 percent of its energy from renewable sources. One problem, however, is that the amount of energy available fluctuates constantly. So some innovators are trying to create a system where demand for energy follows supply, instead of the other way around. Wyoming Public Radio's Stephanie Joyce reports for Inside Energy, a public media collaboration covering energy issues.

JUDY WOODRUFF: The nation of Denmark has been a pioneer in wind energy production. Last year, nearly 40 percent of its electricity came from wind power, and, by 2050, it’s set an ambitious goal of having renewable energy provide 100 percent of the country’s energy.

In the U.S., the Obama administration recently released the Clean Power Plan, which it hopes will lead to more renewable energy production.

Stephanie Joyce traveled to Denmark to see how that country is tackling the challenge. She reports for Inside Energy. It’s a public media collaboration funded by the Corporation for Public Broadcasting, focusing on America’s energy issues.

STEPHANIE JOYCE: Erik Malmkvist’s job used to be a lot easier, before renewable energy. Malmkvist runs the power grid for Bornholm, an island of 40,000 people off the coast of Denmark. The island’s electricity consumption is fairly predictable.

ERIK MALMKVIST, Denmark: You can see people get up in the morning about half past 5:00, then make something. And then they go to eat, and then they just stop. And that’s every day. And that’s the curves we are making.

STEPHANIE JOYCE: But the island’s electricity supply is becoming less predictable. Like most places, Bornholm used to get most of its power from coal and gas, but now more than half comes from wind and solar, which fluctuate constantly.

ERIK MALMKVIST: You can see the wind. And then suddenly it goes up and down all the time. So, it’s very, very unstable.

STEPHANIE JOYCE: As Denmark adds more renewable energy, that mismatch between when electricity is being produced and when it’s needed is a growing problem.

But this sleepy fishing island is home to a cutting-edge energy experiment that could make the variability of wind and solar less of a problem. Bornholm has branded itself the bright green test island and welcomed a series of futuristic experiments focused on the electric grid. The most ambitious experiment is called EcoGrid E.U.

At the demonstration house, project leader Maja Bendtsen shows off how it works.

MAJA BENDTSEN, Project Leader: So, this is some of the equipment that we’re using in the project.

STEPHANIE JOYCE: The EcoGrid project shakes up the traditional relationship between electricity supply and demand. It gets people to use more power when there’s lots available and less when there isn’t. It’s called demand response.

Bendtsen uses a LEGO model to help explain how demand response helps integrate wind and solar into the island’s grid. It’s something she learned about as a kid, when her father installed a wind turbine on their property.

MAJA BENDTSEN: When it was windy, we turned up all the radiator valves full open and could heat the house. But because it was windy and the wind turbine — the wind turbine was spinning anyway, the energy was free and abundant.

STEPHANIE JOYCE: The EcoGrid experiment also relies on using more power when there’s cheap renewable energy available, and less when there isn’t. But unlike when Bendtsen was a kid, no one has to run around opening and closing radiator valves.

MAJA BENDTSEN: A signal goes through to the gateway, and then a signal to the relay saying turn off the heat pump because now the power price is high, and we are within boundaries.

STEPHANIE JOYCE: The equipment gets information about the real-time price of electricity. When it’s high, the equipment turns down the heating and turns it back on again when prices drop, so long as the temperature stays within a specified range, say, 70 to 75 degrees.

MAJA BENDTSEN: Demand response has nothing at all to do with energy savings. It has to do with using the energy when it’s there.

STEPHANIE JOYCE: Which helps with balancing the grid, if it works.

KATHRI MARLUSSEN, Denmark: And this is the power from the EcoGrid. They installed this one when I was signed in to the project.

STEPHANIE JOYCE: Kathri Marlussen lives on Bornholm and is a participant in the project.

KATHRI MARLUSSEN: This is the price now. When it’s red, it’s expensive.

STEPHANIE JOYCE: But although Marlussen can access real-time electricity prices through the project, the devices controlling her heating stopped working months ago. The automation equipment still has some serious bugs.

KATHRI MARLUSSEN: The idea of the project is really good. But then there are some technical problems thus that I can’t use it the way it was supposed to.

STEPHANIE JOYCE: Marlussen sometimes checks the price before doing laundry or running the dishwasher, but those consume almost no electricity compared to heating and cooling.

KATHRI MARLUSSEN: It’s a shame that it can’t work the way it’s supposed to do.

STEPHANIE JOYCE: She’s not the only one who thinks so. Back on the mainland, I met Jorgen Christensen, the chief technology office for Dansk Energi, the Danish energy association. He agrees it’s a shame demand response isn’t ready for prime time.

JORGEN CHRISTENSEN, Dansk Energi: So, we are overinvesting because we are not utilizing the energy that we produce in a smart way.

STEPHANIE JOYCE: Overinvesting in things like transmission lines and backup power plants, which wouldn’t be necessary if demand response worked better. Christensen is confident the technical problems with demand response will get sorted out. But he’s worried that it will take time to convince people of the benefits, maybe too much time, given the country’s renewable energy goals.

JORGEN CHRISTENSEN: If I would ask my sister whether she would have a flexible or smart charging of her electric vehicle or of heat pump today, she would say, well, I haven’t heard about it today. So that’s where we are there.

JACOB OSTERGAARD, Danish Technical University: On the left side you have a picture of Bornholm, and the green dots are substations.

STEPHANIE JOYCE: On the campus of the Danish Technical University, researchers are tackling both the technological and the consumer side of the problem. They have been analyzing the results of the Bornholm experiment, and are excited about its promise.

But Jacob Ostergaard, who is in charge of the lab, says what they have done so far is just the beginning, and compares it to the nascent cell phone industry.

JACOB OSTERGAARD: You can say that what we have developed is, basically, we have developed the smartphone and one app.

STEPHANIE JOYCE: The app being demand response.

Now, in the analogy, Ostergaard wants to build other apps to transform electricity in the same way the smartphone changed the phone. He thinks, in a few years, we won’t even think about electricity the same way.

JACOB OSTERGAARD: Instead of buying kilowatt hours, which are very difficult to understand how much is a kilowatt hour and what is it, we could buy comfort, for instance. We could buy 21 degrees Celsius in our house.

STEPHANIE JOYCE: That’s a comfortable 70 degrees Fahrenheit.

Whatever those new ways of thinking about electricity end up being, more likely than not, you will find them on Bornholm first.

For the PBS NewsHour, I’m Stephanie Joyce in Bornholm, Denmark.