Today I met with Ari, an engineer at Nordurorka (it means “Northern Power”), to learn more about Akureyri’s hot water system. This means it is dealing with water from low temperature fields, a different system than at the power plants where electricity and hot water are co-generated. Their office sits at the top of the town, where they can see up to the mountainside from where their fresh cold water flows. Their headquarters is a narrow cylinder with a light well at the center. Ari showed me the real time graphical interface that shows information about each borehole: pressure in pipe, temperature of water, current rate of flow of water, and more.
Q: What services does Norðurorka supply, and to where?
A: Norðurorka supplies electricity, and hot and cold water to Akureyri. They also provide water, (sometimes hot and cold, sometimes just hot) to several other towns in Northern Iceland. In several cases, they pipe hot water many kilometers to reach relatively small towns. The map below shows the areas where they supply hot water:
(Pending: system map here)
Q: What are the costs associated with geothermal hot water for the distribution systems? How does it compare to costs in Reykjavik?
A: In 1986 the cost of hot water was 3 times what it was in the larger and (relatively) more compact city of Reykjavik. Still, it cost them maybe a third of what it would to use imported oil.
Today, hot water costs about 90 kronur per cubic meter in Akureryi, while prices in Reykjavik have risen and are now about 80 kronur, The reason for this rise in prices emphasizes that social and political factors matter just as much, if not more than the availability of natural resources. Ari mentioned something about Reykjavik energy investing in other areas such as fishing. Later, I read an article in the Grapevine (Iceland’s bi-weekly English language paper) that explained this. LINK (pending).
Anyways, back to the Norðurorka. They began supplying hot water in 1977, cold water in 1993, and electricity in 2000. The cold water, as I mentioned, is from just uphill. The majority of the hot water comes from 20 kilometers away at Hjelteyri. They have 10 boreholes in total. Typical boreholes go 230 meters down and include a pump. They have one special borehole in an area where the groundwater is deeper that goes down to 390 meters, and another that actually draws water up at 104 degrees celcius (above boiling. This supplies for all of the hot water demand. In 2003, there were 3 very cold weeks in February where they were utilizing all of their pumps as well as a back up 12 MW oil boiler. This was extremely expensive, and led to the driliing of 2 additional wells for the following year.
Q: What system brings the water to buildings? What happens after the water is used to heat the homes?
The hot water pipes run under the sidewalks. The predominant method for space heating is radiators that run along the wall and under windows.
They re-inject only about 10% of the water to the hot water areas. Another 40% goes back through the cycle as they use it to mix with the hot water that is pumped up (this brings it down to a temperature that is usable for domestic spaces). The other half of the water goes into the sewage system, as the same hot water for heating is used for showering and hot water.
Q: Are there currently challenges that Norðurorka is currently facing? Or that they forsee arising in the near future?
No, things are running smoothly.