WOWAZAAA!!! Today was the main highlight of the trip so far. Such a statement, but I have been looking forward to this and Hans pulled through!
Bright and early in the morning, we left for the boat trip to see the offshore wind turbines that we couldn’t see last week. It was the perfect day, not too windy and clear skies. The wind turbines blew my mind (hehe stole that joke). It was absolutely breathtaking up close, and actually being able to go inside the turbine was surreal. I’m not going to say much more because I really just let myself live in the moment and enjoy the boat ride without getting bogged down in the technical intricacies.
*Inserts obnoxiously large pictures of wind turbines*
We then visited a power station owned by DONG Energy. Note the elevator had the floors labeled by their metric height, which I thought was interesting. We got hard hats, safety glasses, and radio headsets that I was way too excited about.
This site visit I was pleasantly surprised by how much I enjoyed it. Perhaps part of this was because the presentation was delivered by Gitte Højgaard-Nielsen in a very clear manner that helped simplify a very technical topic. DONG Energy is largely involved with the production of wind, bioenergy and thermal power. By 2030, they plan to have converted all their power stations from coal to biomass.
There are two units that make up this power station, which was commissioned in 1990 and 2002. The first unit was originally built as a coal-fired plant, but now burns wood pellets. I found it interesting that biomass can run on the same machines as coal. The second unit is a modern multi-fuel plant that can use wood pellets, straw, natural gas, and oil. Despite the switch to biomass, there is still a need for oil as a start-up and reserve fuel.
The total production capacity is 797MW electricity and 932MJ/s heating. Generating both heat and power allows up to 89% fuel efficiency. This plant mainly produces heating for roughly 215,000 households through the district heating system, which is distributed by local cooperatives. Electricity is produced as a backup to wind turbine power.
In contrast to the previous solar thermal plant visit, it was intriguing to learn more about biomass, and how it is used at this CHP plant. The primary fuel used is wood pellets made from sawdust pressed using steam. We were told it actually cost 3 times as much as coal, but it is tax exempted when used to produce heat. The benefit of biomass fuels is that it is CO2 neutral, which means the CO2 emitted will be reabsorbed by the trees and crops that are replanted to maintain the CO2 balance; however, I am skeptical about this claim.
Straw is the second type of fuel used. The straw storage area is shown above, where we saw the straw being unloaded off trucks by a machine. Later, the straw would be automatically taken to the boiler. Approximately 130,000 tons of straw is combusted per year!
In addition, we were given an overview of the production process. First, the biomass fuel is fed into a fuel mill, which crushes the fuel into dust. Hot air blows the dust into the boiler burners. Due to the combustive nature of dust, it ignites and burns at 1500 degrees Celsius! The boiler walls have water flowing in them, which changes into steam due to the high temperature.
The steam drives the turbine blades and subsequently the generator, which produces electricity using electromagnets. The steam is either fed into district heating heat exchangers to heat water for the district heating system (stored in storage tanks) or to a condenser, where it is cooled using sea water.
On our tour, we visited the control room. Most of the graphic displays were provided by Emerson and some were from ABB.
I was able to recognize several of the monitor displays since I have worked on the making the graphics for turbine control systems at ABB. It was gratifying to be able to see the application of technology I have experienced from the backend now from the control room of a power plant.
For our free time, a group of girls and I went to check out Freetown Christiania. It is a small town that declared its independence and is a self-governing community, where most notably cannabis is freely traded and smoked. Since we were kinda lost trying to find the place, we were low-key freaked out cause we definitely stood out. However, I felt like the town was truly unique and some people came back with some really cool stories from talking to local people who lived there. After walking through, we bolted for dinner at paper island again.
To end the night, I really wanted to check out special vegan places in Copenhagen, and Simple Raw was one that was still open! Cultural note – most businesses seem to close relatively early.
Maddy thankfully joined me on vegan dessert endeavor, and we shared a dessert sampler and each got hot chocolates. BEST HOT CHOCOLATES like EVARSSS. The desserts were also really rich, and we couldn’t even finish cause we were so stuffed by the end. Definitely recommend this place!!!
Now I wish I had gotten a chance to visit more vegan restaurants here, but it’ll be easier once I’m on my own in London to venture off. So surreal to think that this was our last day in Copenhagen. I don’t want to leave 😪
I’m ready to see what Sweden has to offer though…