Research on river biota in Þjórsá
Environmental research is an important part of our operations. Extensive information is required at the initial stages of exploring any potential power project. This enables us to develop the individual aspects of each power project and minimises the environmental impact. Landsvirkjun has been involved in research and preparation measures for the lower region of Þjórsá, below the Búrfell Hydropower Station, for years. Three power projects are being explored: Hvammur, Holt and Urriðafoss. All these potential projects have been categorised as “under consideration” by the Master Plan for Hydro and Geothermal Energy Resources in Iceland.
Landsvirkjun has monitored the biota of the Þjórsá River for years and has carried out extensive research on fish stocks in the river since 1993.
Information on the migration and population of salmon in the lower region of Þjórsá must be collected before any potential power project is developed within the area. This information is an important factor in assessing the need for any mitigation measures required to minimise the environmental impact to the area. Design features include a juvenile fish bypass system, a fish ladder and fish-friendly turbines. Other measures will focus on minimising any disturbance to aquatic life in the area.
Monitoring the salmon population
The Institute of Freshwater Fisheries has verified the correlation between angling numbers and the fish stock population in salmon fishing rivers used for angling. However, the Þjórsá River is mostly used for net fishing and there is no available data that shows the correlation between net fishing and fish stock population. The number of salmon in the Þjórsá River is therefore unknown.
670 juveniles were tagged in the Kálfá River in an attempt to assess the total population of salmon in the Þjórsá River.
Automatic fish counters are the most effective tool to assess the fish stock population in downward flowing water. The counter would be located a short distance from the estuary where all fish pass through on their migration up-river. However, the Þjórsa River has a high discharge and a long distance between the banks of the river which makes it difficult to install a conventional automatic fish counter. We constructed a fish ladder by the Búða Waterfall in 1991 which has an automatic counter. However, the fish ladder is located in an area far from the estuary and it is unclear what percentage of salmon pass through the fish ladder.
Data from the counter can therefore not be utilised to assess the fish stock population in the river.
The Institute of Freshwater Fisheries proposed that the salmon stock population in Þjórsá could be measured by tagging a known percentage of juveniles as they migrate to the sea. The number of returned adults would then be assessed a year later and the percentage of tagged and untagged fish caught or counted in the automatic fish counters would then be compared.
Tagging began in the Kálfá River in 2012 when 670 juveniles were tagged by inserting a steel marker into the snout of the fish and their adipose fin was clipped. Research has shown that the tags do not affect the juveniles and fin clipping does not affect their chances for survival.
Fish that pass through the counter are categorised as tagged or untagged via photograph. Am emphasis is also placed on assessing the number of tagged fish caught during fishing in the river.
A barrier and automatic fish counter were set up in Kálfá. The barrier covers the entire area between the river banks and fish are therefore directed to pass through the counter.
Opportunities in diverse utilisation
In 2014, the geochemist Sigurður M. Markússon was appointed as project manager for the development of diverse utilisation of geothermal resources. We hope that the project will lead to improved utilisation of all the valuable components of the geothermal resource.
We have placed an emphasis on exploring the possibilities for diverse utilisation in geothermal areas in the northeast of Iceland where the Company operates two geothermal stations. Industrial development and geothermal utilisation are developed in cooperation with the local community. An awareness of the potential for improved utilisation of geothermal energy has grown in the last few years and the opportunities offered by the concept are increasing with every year.
The accessible thermal energy, for diverse utilisation purposes, at the Krafla Station is estimated to be anything up to 200MWh.
Geothermal power stations are mostly associated with domestic heating and other infrastructure needs in Iceland. The areas surrounding Landsvirkjun’s stations do not require heating utilities but there are tremendous opportunities in utilising the electricity generated by utilising the geothermal resource.
Production in many other countries is driven by the burning of fossil fuels and the resulting emission of greenhouse gases. Multi-utilisation offers an environmentally friendly option for industry sourced from renewable energy resources and without significant environmental impact.
Hot water, steam and gas can be utilised by a number of industries requiring energy. These industries include agriculture, the algae cultivation industry, further processing of raw materials and fuel production from carbon dioxide emissions from the power stations. Further utilisation could also support tourism within the geothermal area. The nature baths in Mývatn are a prime example of this as they utilise the spillover from the Bjarnarflag Geothermal Power Station.
Utilising natural resources in a more efficient manner
The utilisation of all the valuable components of the geothermal resource creates synergy, therefore increasing the efficiency of utilisation, minimising environmental impact and increasing overall operational efficiency.
Air quality monitoring during volcanic activity
Landsvirkjun has conducted extensive research on the environment in cooperation with universities, research institutes and independent experts. The objective is to increase expertise with regard to the environment and to monitor the effects of human activities on the environment.
Landsvirkjun’s cooperation with various research institutes as a result of the volcanic activity in Holuhraun is a perfect example of how the research community can share expertise, facilities and equipment.
We conduct a diverse range of research including air quality monitoring, pertaining to geothermal utilisation. The concentration of hydrogen sulphide (H2S) in ambient air is monitored, the source of which is active wells and the natural discharge from geothermal areas and volcanic eruptions.
We operate five air monitoring stations in the northeast. Two stations are located in Reykjahlíð by Mývatn, one in Kelduhverfi and one in Þeistareykir. The fifth monitor has previously been located in Reykjahlíð but was lent to Akureyri to monitor pollution from the Holuhraun eruption.
The concentration of hydrogen sulphide in Landsvirkjun’s research areas did not rise above the set health limit of 5 µg/m3 in 2014.
Research results show that hydrogen sulphide levels did not rise above the set health limit of 5 µg/m3 (±3 µg/m3), in 2014, given that the accuracy of measurement is ±3 µg/m3. The daily (24 hour) maximum, moving average concentration of hydrogen sulphide never rose above the set health limit in accordance with regulation 514/2010, 50 µg/m3.
Sulphur dioxide (SO2) is one of the main volcanic materials expelled by the volcanic eruption at Holuhraun. Landsvirkjun’s air quality monitors can measure hydrogen sulphide levels (H2S) and sulphur dioxide levels (SO2). However, the measured level of SO2 becomes less accurate when both gases are measured concurrently; particularly when there is a variable concentration of sulphur dioxide. A substantial drop in sulphur dioxide within a short period of time can result in inaccurate results, showing an increase in hydrogen sulphide values. However, a substantial rise in sulphur dioxide within a short period of time can result in inaccurate results, showing a decrease in hydrogen sulphide values. Sulphur dioxide level monitoring, pertaining to geothermal stations therefore also becomes less accurate. We will consider these factors when analysing future air quality monitoring results.