Today I visited my first geothermal power plant. ever. The company plant name is HS Orka HF. We were led by Þorgrímur Stefán Árnason. He gave us a most informative talk about how their plant is run, and how they recycle just about every bit of their excess steam, water, and carbon emissions. I took a few notes so let me try to explain them here. I guess I could tell you all about the history of the plant, but I will keep that part short as the actual geothermal activity as a form of renewable energy is much more important. You can click here for some pretty awesome pictures inside this particular plant. They have nothing to hide.

During the energy crisis of the 70’s, Iceland looked into the use of its wealth of geothermal activity for energy. Actually, they first looked into it merely for heating, then advanced to energy use. So, at this particular plant, due to its proximity to the ocean, the water and steam that is “pumped” from the ground must be separated. Meaning that all of the minerals must be removed before anything else.

So to start, the magma in the ground heats the water to well over 200*C. Bore holes were drilled into the ground where potential hot spots may be located (which in Iceland, is pretty much anywhere). The deepest hole at this area is to be about 400m. These holes were used for hot water production in the thermal energy exchange plan for the nearby towns people. Over time, the water table fell, but the heat system stayed the same. They then drilled directly into the steam pockets. Steam heat and boiling water is extracted from the ground as a “brine” (water/steam mixed with ground minerals). The brine is then separated, the steam and water used as energy and heat, then pumped back into the ground for another round. Of course that is very basic.

The “wastewater” that consists of all the minerals is pumped into a lake. It was first thought that this water was an environmental hazard, then someone got the bright idea to actually bathe in the water to treat their psoriasis. It seemed to work, and since the 1980’s the Blue Lagoon Spa has been in full force. It is believed that the high mineral and algae content of the wastewater is an excellent source for skin health. These are the mineral count stats that I got from the Blue Lagoon website:

Blue Lagoon geothermal seawater Concentration of major elements. (mg/kg of fluid)

• Silica (SiO2) 251
• Sodium (Na) 7.643
• Potassium (K) 1.177
• Calcium (Ca) 1.274
• Magnesium (Mg) 0,60
• Carbon dioxide (CO2) 11,4
• Sulphate (SO4) 31,8
• Chlorine (Cl) 15.740
• Fluorine (F) 0,18

Total soluble Chemicals 25.800–Other elements are in trace amount

ok, so they say that continual sampling of the water shows no signs of bacteria due to the high mineral content. It still grosses me out to basically take a bath with hundreds of other folks at the same time with the same bath water. I guess that is another story.

In other geothermal news:

The process of heating a home goes like this:  Heat energy released by the pressurized fluid is channeled through a home’s ductwork  for distribution to radiant baseboards, in-floor tubing, or radiators. This water is also their source of hot water. ALSO, some homes are now starting to install pipes under their sidewalks and driveways to keep ice from forming in the winter. The cost of geothermal energy is so minimal that Icelanders can afford to do this.

The hot water being pumped to houses can get up to 103*C and does not need to be treated.

and lastly:

Today, the total production capability of the energy plant in Svartsengi is 75 MW in electrical energy and about 150 MW in thermal energy. How is that for renewable energy?? Don’t worry, there is more to come……….