I love to travel, but when you start looking like your passport photo, it's time to go home. There are other signals that you have been on the road way too long, too. Do you have to look at your cell phone to determine the day? Can you remember your hotel room number when asked by the front desk? Or perhaps you wake up in the middle of the night and don't have a clue where you are. If so, you have zoned out.

I hit this stage on a recent European trip. It was a great trip, but it was demanding. I spent about a week there and racked up close to 20,000 miles by the time I returned home, but I learned so much about the latest advancements in high-voltage direct-current (HVDC) technology that is was worth it. Still, I did look like my passport photo!

Why Europe? Well, a great deal of what is happening in HVDC technology is taking place there. The European Union (EU) is pushing the boundaries for integration of DC into the AC grid, which will be coming to a grid near you soon.

Wind is the driving force behind this endeavor. Offshore wind farms are getting bigger, both geographically and rating wise, and they are also moving further from shore beyond the capabilities of AC submarine cables. In addition, underground cable advancements from HVDC schemes are changing the game plan. In Sweden, utilities are putting overhead AC lines underground, selling the aboveground right-of-way and making a profit.

Change of Focus

As I said, I love to travel. It seems like I always gain a new perspective to some subject I thought I knew all about. And this trip did not disappoint me. What I didn't expect to find was such important social implications associated with the application of HVDC technology.

One of the first things I noticed when discussing a new HVDC project with colleagues was that the conversation would describe the physical ratings (i.e., volts, current, power, etc.) and then shift to the amount of CO₂ the project offset. The EU is using HVDC to bring remote renewable power to the load centers, reducing the carbon footprint in the process.

CO₂ reduction goes all the way to the customer level, too. This was apparent in my first hotel room. When I went to my room and hit the light switch, nothing happened. I saw a card holder for the room key near the door. I put my room key in, and the lights came on.

This is subtle. If you don't insert the key, there won't be any electricity in the room. Also, when you leave the room, you remove the key and the lights go off. I found this same system in every hotel room I stayed in.

One day, I stopped for a quick lunch at a Swedish fast-food emporium (great hamburger, by the way). At the bottom of each selection, there was an estimate for the amount of CO₂ each selection represented. So there is awareness from the utilities and the customers, and HVDC is playing a huge part in the renewable market here to support this effort.

Politics and the Environment

Previously, I mentioned that HVDC was helping on the political front. I had an invitation to see the Estlink converter station located outside of Tallinn, Estonia. Estonia was part of the Soviet Union until 1991 when it gained its independence. Estonia uses oil shale-fired power plants to generate electricity, but it depends on major interconnections with Russia. The oil shale produces CO₂, and the Russian interconnections are subject to the winds of politics.

Estlink is a 350-MW interconnection using HVDC Light transmission technology between Finland and Estonia connecting the Nordic and Baltic power markets. The Nordic power grid has a lot of clean wind and hydro power, which falls into the CO₂ reduction goal utilities are focused on. The 650-MW Estlink 2 is under construction with commissioning scheduled for 2014. The HVDC transmission links offer a way to ensure an electric power that is independent of politics (i.e., power comes from multiple sources).

Lithuania had a nuclear generating station built when it was part of the Soviet Union. It also has a fossil-fuel plant using natural gas, heavy fuel oil and bitumen-based fuel. The nuclear plant was closed in 2009, and the fossil-fuel plant doesn't meet EU environmental guidelines, so Lithuania also relies on interconnections with Russia. The NordBalt HVDC link will give Lithuania a 700-MW interconnection to clean wind and hydro power from Sweden with commissioning set for 2015.

There are also discussions in places like India and Bangladesh for HVDC links between the two countries for power transfers: Improving communications improves relationships. It gives new meaning to power for peace.

I went to Europe with the goal of improving my understanding of the advancements in HVDC technology. What I discovered was that HVDC is also playing a role in meeting societal concerns in reducing our carbon footprint. Let's put our technical skills into play, not only to build a better energy system but also to make ours a more livable planet.