Oberhasli power plants

Kraftwerke Oberhasli AG
legal form	Corporation
ISIN	CH0350030422
founding	1925
Seat	Innertkirchen BE Switzerland
management	Daniel Fischlin (CEO) Barbara Egger-Jenzer ( Chairman of the Board of Directors )
Number of employees	410
sales	143 million SFr.
Branch	power supply
Website	www.grimselstrom.ch
Status: 2019

Oberhasli power plants
Reservoirs of the Oberhasli power plants: top left: Oberaarsee, left: Grimselsee , right: Räterichsbodensee
location
Canton of Bern , Switzerland
Coordinates	660746  /  172509
country	Switzerland  Bern
Waters	Grimselsee , Oberaarsee , Räterichsbodensee , Gelmersee , various smaller lakes, Aare , tributaries from the Haslital and the Gadmertal
Data
Type	Multi-stage storage power plant group with pumped storage plants and run-of- river power plants
Primary energy	water
power	Total output 1318 MW
owner	½ BKW Energie 1 ⁄ 6 IWB 1 ⁄ 6 Energie Wasser Bern 1 ⁄ 6 City of Zurich
operator	Grimsel Hydro
Project start	1906
Start of operations	1962
Energy fed in 2019	2406 GWh
Website	grimselstrom.ch
was standing	2020

The Kraftwerke Oberhasli AG (KWO) is an operator of hydroelectric power plants in Switzerland . With 13 hydropower plants and eight storage lakes , it will produce around 2,400 gigawatt hours (GWh) of electrical energy in 2019. Its headquarters are in Innertkirchen in the canton of Bern .

History and technology

Founder share of Kraftwerke Oberhasli AG from June 20, 1925

The excellent suitability of the Grimsel and Susten areas for the use of water power was recognized as early as the end of the 19th century : abundant rainfall, large terrain chambers, stable granite subsoil and large differences in altitude over a short distance. The United Kander- and Hagneck-Werke , a predecessor company of BKW , prevailed against other applicants and received the right to use the hydropower of the Aare and its tributaries from the Grimsel to Innertkirchen in March 1906 . One of the competitors of the later BKW was the Lotzwil entrepreneur Robert Müller-Landsmann, who later had the Wynau an der Aare power plant built.

On June 20, 1925, BKW from Bern founded Kraftwerke Oberhasli AG, based in Innertkirchen, in which the canton of Basel-Stadt also participated in 1928 and the city of Bern in 1930 , followed by the city of Zurich in 1938. The ownership structure has remained unchanged since then. BKW Energie owns half, IWB , Energie Wasser Bern and the City of Zurich each own a sixth of KWO. The form of organization, in which several legal entities participate in a stock corporation for the joint utilization of hydropower , was later used in other power plant projects and is known in Switzerland as the partner plant .

Expansion stages

The power plant group was built in three expansion stages. In a first step, the Grimsel, Gelmer, Räterichsboden, Mattenalp and Oberaar reservoirs were built in the Aare valley and the associated power plant centers in Grimsel, Handeck and Innertkirchen. The second step included the utilization of the water from the Gadmental. The third expansion step was initially planned under the name Grimsel West . It should improve peak energy production and store more water from the summer runoff for use in winter. The project failed due to resistance from environmental associations that campaigned for the preservation of the Sunnige Aar pine forest . It was no longer pursued in 1999 and was replaced by the KWO Plus expansion program , which intervenes less strongly in the moorland.

First expansion phase 1925–1954

At the end of this expansion phase, the power plant group will comprise four power plants with a total output of 493 MW. In the five larger reservoirs, 208 million m³ of water from the Aare valley could be stored, which corresponds to an energy content of 630 GWh. The average annual production was 1170 GWh, 90% of which could be provided as peak energy.

Plant scheme of the KWO, status 2010. The construction projects for the Innertkirchen 1 extension and the Handeck 2 extension have been implemented. Other construction projects not shown here are in preparation or underway.

1925–1932: Grimselsee, Gelmersee and Handeck 1

The dam walls of the Grimselsee and Gelmerseee , the 5.2 km long connecting tunnel between the two lakes and the Central Handeck 1 were built. In the machine house, which is in the open air, four vertical-axis machine sets with Pelton turbines are installed, which at that time had a combined output of 92 MW. The machine house was connected to the substation in Innertkirchen via a 50 kV high-voltage line. The Spitallamm dam of the Grimselsee was with a height of 114 m at the time of completion the highest dam in Europe. The Gelmerbahn , one of the steepest funiculars in the world , was also built with this stage .

1939–1943: Innertkirchen 1

During the Second World War , the Innertkirchen 1 power plant was built as the second stage of the power plant group. The machine house was first laid out in Switzerland as a cavern center and was the model for other power plants of this type. The water came from the newly built Handeck equalization basin via a 10 km long tunnel to the Kapf moated castle and from there via a 1.9 km long armored pressure shaft to the headquarters, where there were initially three and later five machine groups, each with an output of 47 MW. The maximum 235 MW output of the headquarters was transferred to the Innertkirchen substation using a 150 kV high-voltage line. With Innertkirchen 1, the power plant group had a total output of 294 MW and could produce 660 GWh annually.

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  Expansion of the facilities in 1943

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  Machine room of the headquarters Innertkirchen 1

1947–1950: Räterichsbodensee, Mattenalpsee and Handeck 2

After the Second World War, the plant was enlarged by the Innertkirchen 2 underground power plant. Additional water was stored in the newly created Räterichsbodensee . The Mattenalpsee was built in the Urbachtal, the water of which is fed through a feed tunnel into the Kapf moated castle. Four vertical-axis machine sets with Pelton turbines are set up in the headquarters. Each machine set had an output of 33 MW. The voltage of the transmission line to Innertkirchen was increased to 150 kV.

1947–1950: Totensee

In 1949 and 1950 a dam was built at the Totensee and the water that naturally flows into the Rhone was channeled into the Grimselsee. Previously, the water was used by the Gletsch small hydropower plant, which received energy usage rights in return for using the water.

1952–1954: Grubenbach and Bächlisbach water catchments

The water from the Grubengletscher is collected below the Grubensee and fed into the Bächlital through a 2.2 km long tunnel. There it is collected together with the water of the Bächlisbach from the Bächli Glacier in the Bächlisee and led into the Grimselsee via a 1.36 km long tunnel.

1950–1954: Oberaarsee, Trübenensee and Grimsel 1

In the 1950s, the dam of the Oberaarsee and the Grimsel 1 power station were built. The Trübenensee also received a small dam; its water is fed into the 5.4 km long supply tunnel from Oberaarsee to the Grimsel moated castle. A 1.6 km long pressure shaft leads from the moated castle to the Grimsel 1 cavern center, where there was a machine group with a horizontal axis with an output of 34 MW. There was also a 19.5 MW pump in the control center, which could pump water back from the Grimselsee – Gelmersee connecting tunnel into the Oberaarsee. The power plant was connected to the Innertkirchen substation via a 150 kV high-voltage line.

Second expansion phase 1952–1979

At the end of the second expansion phase of the power plant group, it was also possible to use the water from the Gadmertal. At the end of the expansion, the group comprised seven control centers, which together could generate 582 MW and generate 1.5 GWh annually.

1952–1954: Trift tunnel

After the two reservoirs in Räterichsboden and Oberaar had been built, the Innertkirchen power plant ran out of water in summer. In order to replace this, the previously unused water from the Gadmertal was fed into the inlet tunnel of the power plant. For it was turning water which of Steingletscher originating Gadmerwasser and from Triftgletscher native pasture water caught and led with a 12.5 km long tunnel to the window Rotlaui in pressure tunnel Handeck-Innertkirchen.

1958–1960: Fuhren

A power plant was built in Fuhren in the Gadmertal to use the water from the upper Gental . For this purpose, the Engstlensee was provided with an underground lakeshore that allows the lake to be lowered by five meters during the winter months. The adit of the lake empties approximately 250 m below the natural lake outflow into the Gental water , which is collected after another 480 m and, together with the water from other streams, is fed to the Teuflaui compensation basin. From there, a 2.6 km long inlet tunnel leads into the neighboring Gadmertal to the Birchlaui moated castle, where a 1.9 km long pressure pipe leads to the Fuhren power station . The underwater is channeled through a counterpressure tunnel into the tunnel window Schaftelen of the Steinwasser – Trift intake tunnel. The water can then either be used in the Hopflauenen and Innertkirchen 2 power plants or pumped into the Räterichsboden reservoir via the pump turbine from Handeck 3 . In the headquarters in Fuhren, an additional pump can move Gadmer water from an equalization basin into the Trift tunnel during off-peak times.

1962–1967: Hopflauenen

In order to be able to make better use of the large runoffs in the Gadmental in summer, another power plant was built in Hopflauenen. Two underground reservoir chambers were built at the Trift water catchment, from where an almost four-kilometer long inlet tunnel leads to the Speicherberg moated castle, from where an 890-meter-long pressure shaft leads to the underground headquarters in Hopflauenen in Gadmertal. The water is processed by two Pelton turbines. Another separate supply line leads from the other side of the valley water from the Leimboden equalization basin to its own turbine. The underwater of both levels is returned to the Hopflauenen equalization basin.

1964–1968: Innertkirchen 2nd

The free-standing Innertkirchen 2 headquarters is the lower level of the Hopflauenen headquarters. The water is fed from the Hopflauenen equalization basin via an almost four-kilometer-long tunnel to the moated castle above Innertkirchen, from where an approximately 600-meter-long pressure shaft leads into the power plant. The water is processed by two Francis turbines .

1970–1974: Expansion of Grimsel 1

The central Grimsel 1 was equipped with an additional group of machines with a capacity of 7.5 MW, which processed water from the Grimselsee into the Räterichsbodensee, with which additional water could be made available for the central Handeck 2. The machine group was replaced as part of the KWO Plus expansion .

1972–1977: Handeck 3

The Handeck 3 power plant consists of an Isogyre pump turbine and a diagonal pump . It serves to better connect the Gadmertal power plants with the Aare valley power plants. In turbine operation, Handeck 3 can process water from the Räterichsbodensee, whereby the underwater can be released in the direction of Trift or in the direction of Innertkirchen 1. With the transition in the direction of Trift, the central Innertkirchen 1 will be relieved and free capacities in the central Hopflauenen and Innertkirchen 2 can be used. Handeck 3 pumps water from the Gadmertal into the Räterichsbodensee, which creates the possibility of storing water from the Gadmertal even though there are no reservoirs there. This function is particularly important in summer, when there is more water in the Gadmertal than can be processed there.

A diagonal pump installed in 1976 was able to pump water from the Handeck equalization basin towards Trift.

1975–1978: Expansion of Hopflauenen and Innertkirchen 2

By transferring water from the reservoirs in the Aare valley to the Gadmental, the installation of a further machine group in the central Hopflauenen and Innertkirchen 2 was certainly worthwhile

1973–1979: Grimsel 2

The Grimsel 2 pumped storage plant created the possibility of pumping water from the Grimselsee into the Oberaarsee during off-peak periods. The system is a pure circulating system, which means that the water processed in the turbine operation was previously pumped up into the Oberarsee and does not come from the natural tributaries of the Oberaarsee. In conjunction with nuclear power plants, the function enables the energy generated during off-peak periods to be temporarily stored in order to be able to call it up again during peaks in demand. Four sets of machines are set up in the headquarters, each consisting of a Pelton turbine wheel, a motor generator and a pump wheel. In connection with the construction of Grimsel 2, the voltage in the power transmission network between the group's power plants was increased from 150 kV to 220 kV.

Project Grimsel West

The core of the project submitted for the granting of the concession was to increase the storage volume of the Grimselsee by building an additional 203 m high arched weight wall approximately 1.3 km west of the existing Spitellamm and Seeuferegg dams. This would have created two reservoirs, a new reservoir called Grimsel West with a volume of 410 million m³, the lake level of which is 2020 m. ü. M. would have been located, and the rest of the existing reservoir with a remaining volume of 44 million m³ with an unchanged maximum stowage rating.

The water from Grimsel West would have been processed with four turbines in the Handeck IV cavern center, and a pump center with four machine sets would have pumped water from the Trift tunnel and other tributaries in the Handeck into the Grimsel West reservoir. A new tunnel system would also have been built from the Handeck to Innertkirchen, where the water would have been processed in a new central Innertkirchen 3 - not to be confused with the small power plant of the same name built in the 2010s.

A new Grimsel IV center with two pumps would have been built under the Gerstenegg, which would have pumped Steinwasser and Triftwasser from the Gadmertal to Grimsel West. A new tunnel system with a 5 million m³ compensation basin at Obere Trift would have been built to feed the water. Furthermore, a pump turbine would have been housed in Grimsel IV, which would have pumped water from the Räterichsboden to Grimsel West in summer and in the opposite direction in winter. A Francis turbine would have used water that would have been directed from Grimsel West to the Gelmersee. More water would have been directed from the new Gauli water intake below the Gauli Glacier to the Grimsel IV headquarters.

In 1987, the KWO calculated an investment of CHF 1.9 billion for the entire project. and a construction period of 15 years. The winter energy production would have increased from 753 GWh to 1912 GWh, the maximum output of the turbines would have increased from 959 MW to 1887 MW.

The license application for the project was submitted in 1988, which was followed by objections from several environmental associations. In 1991 an amended Project 90 was submitted, against which the Guttannen municipality objected. In 1999 the expansion project was replaced by the new KWO Plus project .

Third expansion phase of the KWO Plus from 2002

The third expansion stage under the name KWO Plus primarily enables an increase in peak energy production, but also aims to improve flood protection by increasing the storage capacity of the reservoirs. This means that more water that occurs in summer can be stored for electricity production in winter. In addition, some small power plants will increase the utilization of the available energy reserves.

2002–2007: upgrading Innertkirchen 1

In a first step, a second tunnel was built parallel to the existing one between Handeck and the Kapf moated castle, increasing the cross-section of the supply line to the moated tower and thus slowing the flow rate of the water and thus reducing the friction losses in the tunnel system. The existing tunnel has a diameter of 3.3 m, the new additional one of 4.3 m. Furthermore, the shafts and impellers of the turbines and the machine transformers of the sixty-year-old headquarters were renewed.

2003–2007: upgrading of the Grimsel 1

The turbine from the 1950s, which processed the water from the Grimselsee, had too little swallowing capacity so that part of the water had to be transferred unused into the Gelmersee. The existing machine group was replaced by a new one that can deliver a maximum of 26.5 MW.

2011–2016: Project Tandem , Innertkirchen 1E and Handeck 2E

The entire headrace tunnel system between Räterichsbodensee and Innertkirchen has been doubled. To this end, 19 km of tunnels had to be built. The Innertkirchen 1 and Handeck 2 centers were supplemented with additional cavern centers, ³ in each of which a vertical Pelton turbine was installed. Innertkirchen 1E has an output of 150 MW, Handeck 2E one of 90 MW. In addition, a new equalization basin was created in Innertkirchen, which allows the processed headwater to be released into the Aare on a regular basis and thus avoids the harmful effects of the suddenly rising or falling Aare level.

In connection with the Tandem project, the Handeck 3 power plant was renovated. The Isogyre Group's outdated, fault-prone control and regulation technology was replaced and the diagnostic pump was shut down. The Isogyre group now mainly serves as a pump for the storage of Gadmertal water in the Räterichsbodensee, the diagnostic pump had lost its importance due to the increased processing capacity of Innertkirchen 1 so that it could be decommissioned.

Because the expansion projects Grimsel 1E and Grimsel 3 were not continued immediately after the Tandem project, in 2016 the KWO cut 50 jobs in the areas of engineering, project management and construction management.

2015–2016: Innertkirchen 3 (reason)

The small power plant uses the slope of Ürbachwassers between the Ürbachsallmend and the Aare valley. The six-nozzle vertical Pelton turbine has an output of 3 MW.

2019–2025: Replacement of the Spitallamm dam

In the case of the Spitallamm arched weight wall on the Grimselsee, it was already discovered in the 1960s that a vertical crack ran through the structure between the benton lining on the water side and the weighted concrete. Instead of repairing the old dam, a new arch dam is being built in front of it. After completion, the old dam wall will not be removed, but flooded.

Handeckfluh small power station

The Handeckfluh small power station is to use the previously unused gradient between the Mattenalpsee and the Handeckfluh moated castle. With an investment of 22.5 million SFr. a completely underground plant with a capacity of 10 MW can be built, which would produce 24 GWh annually. The application for the building permit was submitted in 2017.

Trift reservoir and power station

The terrain basin on the Trift, which was exposed due to the retreat of the Trift glacier due to the change in climate , is to be used for a reservoir of 85 million m³. It will serve both for energy production and to protect the settlements in the Gademrtal from floods that could be caused by tidal waves from the existing glacial edge lake . The danger arises from spontaneous ice breaks of the glacier or rock masses falling into the lake.

The dam is to be built about two kilometers above the existing Trift water intake and is to be designed as a 177 m high, double-curved arch dam. In addition to the water from the Trift glacier, the water from the Steingletscher is also fed into the lake via a new tunnel tunnel. The 425 m difference in altitude between the reservoir and the existing Trift water intake is used by the Trift power plant, which is accessed via an access tunnel from Fuhren. With an output of 80 MW, the power plant will produce 145 GWh per year. The energy, which can be accessed quickly, is required for grid stabilization and to cover peak loads in winter.

The license application for the CHF 387 million project was submitted in September 2017. In March 2020, the Federal Council approved the protection and use plan for the Upper Gadmental, after which the Grand Council of the Canton of Bern is to grant the concession. It is required by the KWO to submit the building application. The KWO does not want to decide on the financing of the project until 2023 and is hoping for support from the Canton of Bern and the federal government. A construction period of eight years is expected for the project.

Grimsel 1E power plant

The Grimsel 1E power plant would double the headrace tunnel system between Grimselsee and Räterichsbodensee, similar to the Tandem project . As of 2013, the investment for the 150 MW pumped storage center would amount to around 155 million SFr. amount. In August 2014, the Bernese Grand Council approved an adjustment of the KWO overall license for power plant construction, but implementation in 2020 was uncertain and was made dependent on the development of electricity prices.

Grimsel power station 3

The Grimsel 3 pumped storage plant would have connected the Räterichsbodensee with the Oberaarsee with three variable-speed 220 MW pump turbines. In 2011 the project would have an investment of 660 million SFr. made necessary and could be built within six years. Although the concession for the power plant was available, its construction was suspended by the Board of Directors in 2013 for economic reasons.

Enlargement of the Grimselsee

The enlargement of the Grimselsee was already planned with the Grimsel West reservoir. After the abandonment of this project, a new project was presented, which provides for raising the dam walls of the Grimselsee by 23 m. This could increase the reservoir capacity from 94 million m³ to 150 million m³, which would enable the storage of an additional 240 GWh. The implementation of the project is dependent on a complaint from the environmental associations pending at the Federal Supreme Court. The decision is expected in 2021 at the latest.

System scheme

Oberhasli power plants
Cloudy Lake Pit glacier Oberaar Glacier Pit Lake Oberaarsee Bächli Glacier Kessiturm W) Hausenegg W) Dead Sea Bächlisee Unteraar Glacier Grimselsee Grimsel 2 PT) Grimsel 2 W) Grimsel Nollen N) Engstlensee Gelmersee various mountain streams F) Grimsel 1 S) + 1E PT) Raeterichsbodensee Gauli Glacier Grimsel 3 PT) Gaulisee Teuflaui A) Mattenalpsee Birchlaui W) Handeckfluh Stone glacier Handeckfluh W) Stein – Trift Z) Steinwasser – Trift Z) Triftsee dam wall Pump socket Fuhren A) Shafts W) Carried S) P) Trift S) Trift F) Trift reservoir chamber Handeck 1 T) Handeck 2E + 2 S) Handeck A) Speicherberg W) Handeck 3 PT) P) Glue bottom A) Rotlaui Hopflauenen L) S) Kapf W) Hopflauenen A) Lush W) Pfengli F) Innertkirchen 2 + 1 + 1E T) Innertkirchen 3 Innertkirchen A) Aare A) Equalization basin S) storage power plant W) moated castle PT) pump turbine F) water intake P) pump Z) inlet tunnel L) run-of- river power station N) supply turbine

Power plants

KWO system scheme. State of the systems in 2010, some systems that were commissioned later are not shown.

The following overview is based on the statistics of hydropower plants in Switzerland from 2020 and the information on the KWO website in May 2020. Expansion projects and decommissioned plants are shown in italics in gray . A link to a map with the location of all power plants can be found at the top right of the article.

Headquarters	Machine set	Type of power plant	function	Upper water	Underwater	Construction time (from – to)	Standard energy capacity in GWh (per year)	Bottleneck capacity in megawatts (MW)	Working height in meters	Flow in m / s
Grimsel 1 ▼	Oberaar	Storage power plant	turbine	Oberaarsee	Raeterichsbodensee	1950-1954 2004-2006	40	34	430	8th
	Grimsel	Storage power plant	turbine	Grimselsee	Raeterichsbodensee	2004-2006	60	32	174	20th
Grimsel 1E		Circulation system	turbine pumps	Grimselsee	Raeterichsbodensee			150	-	-
Grimsel 2 ▼		Circulation system	turbine	Oberaarsee	Grimselsee	1973–1980 2012–2016	600	372	430	100
			pump							77
Grimsel 3		Circulation system	turbine pumps	Oberaarsee	Raeterichsbodensee			660	-	-
Grimsel Nollen ▼		Replenishment turbine	turbine	Grimselsee	Gelmersee	2017	5	1.4	35-60	3
Handeck 1 ▼		Storage power plant	turbine	Gelmersee	Handeck compensation basin	1925-1932	160	48	540	10
Handeck 2 ▼		Storage power plant	turbine	Raeterichsbodensee	Handeck compensation basin	1947-1950 2009-2012	262	126	460	33
Handeck 2E ▼			turbine			2009–2012		90	457	24
Handeck 3 ▼	Isogyre	pumped storage power plant	turbine	Raeterichsbodensee	Compensation basin Handeck Reservoir chamber Trift	1972-1976	390	55	460	14th
			pump	Trift reservoir chamber, Handeck compensation basin	Raeterichsbodensee		18th	50		9
	Pumping station	pump	pump	Handeck compensation basin	Trift reservoir chamber	1976 (closed in 2016)	-	10	-	-
Innertkirchen 1 ▼		Storage power plant	turbine	Handeck compensation basin	Innertkirchen compensation basin	1940-1942 / 2002-2007	720	240	670	43
Innertkirchen 1E ▼						2012-2016		150	665	26th
Trift ▼		Storage power plant	turbine	Triftsee	Trift water intake		145	80	-	-
Drove ▼	Gental	Storage power plant	turbine	Engstlensee Gentalwasser	Steinwasser – Trift inlet tunnel	1958-1960	17th	10	400	3
	Pumping station	pump	pump	Fuhren pump socket			12	4.6	184	2
Hopflauenen ▼	Trift	Storage power plant	turbine	Trift reservoir chamber	Hopflauenen compensation basin	1962-1967	245	82	450	24
	Glue bottom	Run-of-river power plant	turbine	Gental water			22nd	5.8	320	2
Innertkirchen 2 ▼		Storage power plant	turbine	Hopflauenen compensation basin	Innertkirchen compensation basin	1964-1968	170	54	225	30th
Innertkirchen 3 ▼		Run-of-river power plant	turbine	Ürbachwasser	Aare	2015-2016	12	3	131	3
Total			turbine				2387	1318
			pump				631	427

Reservoirs

The KWO uses the water from eight reservoirs to generate electricity from hydropower. The total usable volume of these lakes is 195 million cubic meters. That's a little more than a quarter of the annual rainfall on the KWO property. Expansion projects envisage increasing the storage volume by 80%. This includes raising the dam wall at Grimselsee and building a new dam at Triftsee . There is resistance to both projects from among nature conservation organizations . The project to increase the dam wall at Lake Grimsel is waiting for a federal court decision .

Map with seven of the eight KWO reservoirs. The Engstlensee is about 16 km north of the upper edge of the map

Lakes	Usable volume (million m³)	Energy content (million kWh)	Altitude (m above sea level)
Cloudy Lake ▼	1	4th	2365
Oberaarsee ▼	57	210	2303
Dead Sea ▼	2	6th	2160
Grimselsee ▼ after expansion	94 170	263 510	1909 1932
Gelmersee ▼	13	35	1850
Mattenalpsee ▼	2	6th	1875
Räterichsbodensee ▼	25th	63	1767
Triftsee ▼ Expansion project	85	215	1767
Engstlensee ▼  *)	1	3	1851
Total	195	590
Total	356	982	with expansion Triftsee and Grimselsee
*) Natural lake with an underground lake opening

Equalization basin

The equalization basins serve to create the most uniform possible water drainage in the flowing waters, regardless of the amount of water processed by the power plants. They also decouple two power plants connected in series that do not process exactly the same amount of water. The Innertkirchen equalization basin serves to evenly release water from the entire power plant system into the Aare, thereby preventing damage to the river from suddenly rising or falling water levels.

Equalizing basin	Underwater from	Upper water from	Altitude (m above sea level)
Teuflaui ▼	-	Drove Gental	1733
Handeck ▼	Handeck 1,2 + 2E, Handeck 3	Innertkirchen 1 + 1E, Handeck 3	1301
Glue base ▼	-	Hopflauenen	1201
Drove ▼	-	Run pumping station	1152
Hopflauenen ▼	Hopflauenen	Innertkirchen 2	860
Innertkirchen ▼	Innertkirchen 1 + 1E, 2	-	621

Power generation

According to the KWO's annual reports, the following amounts of energy were generated or used to store water. The development of performance in recent years can also be seen. The maximum daily output will be specified until 2012, and the installed turbine output from 2013.

year	Energy output [GWh]	Pump energy [GWh]	Output [MW] up to 2012: maximum daily output from 2013: installed output
2008	2221	731	896
2009	2269	716	813
2010	2211	792	868
2011	2107	708	893
2012	2312	691	788
2013	2255	675	1125
2014	2037	631	1125
2015	2266	563	1125
2016	2130	781	1317
2017	2225	772	1317
2018	2149	551	1318
2019	2406	631	1914

Green electricity certification

1600 GWh of KWO's electricity have been certified as energy from renewable sources with the naturemade basic label since 2005 .

Business areas

Grimsel Hydro

Grimsel Hydro is a service company for the maintenance, optimization and new manufacture of impellers as well as for revisions and repairs of hydraulic machines and closing elements. Originating from the “turbine workshop” created for its own inspection needs, Grimsel Hydro now also offers its services externally on the market.

Grimselwelt

The KWO summarizes its commitment in the tourism sector under the catchphrase Grimselwelt . These include the KWO's power plants and former works railways, which have been opened for tourism, as well as bridges, hiking trails, restaurants and hotels:

• Meiringen-Innertkirchen-Bahn (MIB)
• Gelmerbahn
• Triftbahn
• Handeck – Gerstenegg cable car
• Tällibahn
• Children's and family hotel Handeck
• Historic alpine hotel Grimsel Hospiz
• Restaurant and Berghaus Oberaar
• Alpine hut Bäregg
• Hospice visitor center
• Trift Bridge
• Reservoir visit

Web links

Commons : Kraftwerke Oberhasli  - Collection of images, videos and audio files

• Kraftwerke Oberhasli AG

Individual evidence

1. ↑ Kraftwerke Oberhasli AG. In: Commercial Register. Canton of Bern, accessed on May 15, 2020 . 
2. ↑ ^{a b c} annual reports. In: Grimselstrom. KWO, accessed on May 15, 2020 (Swiss Standard German). 
3. ↑ ^{a b c d e f g h i j k l m n o} Hans Fankhauser: The stages of the development of water power Oberhasli before 1970 . In: Schweizerische Bauzeitung . 1979, doi : 10.5169 / SEALS-85442 .
4. ↑ Kraftwerke Oberhasli AG: The expansion of hydropower in the Gental and Gadmental with the Fuhren power station . 1961, doi : 10.5169 / SEALS-65615 .
5. ↑ How it all began ... Siemens Schweiz AG, accessed on May 16, 2020 . 
6. ↑ Arvenwald Sunnig Aar. In: UNESCO World Heritage Jungfrau-Aletsch. Retrieved May 24, 2020 . 
7. ↑ From Grimsel West to «KWO plus» . In: Nature conservation organizations (ed.): Grimsel in danger . S. 6 ( energiestiftung.ch [PDF]).
8. ↑ According to the text in the graphic of the overview length profile of the Oberhasli power plants (as of 1943)
9. ↑ The expansion of hydropower in the Gental and Gadmental with the Fuhren power station . In: Schweizerische Bauzeitung . tape 79 , no. 44 , November 2, 1961, pp. 755 , doi : 10.5169 / seals-65615 .
10. ↑ ^{a b} IUB Engineering AG (Ed.): Upgrade of the Grimsel 1 power station . December 2014 ( engineering-group.ch [PDF]).
11. ^ The Handeck III hydropower plant of the Oberhasli power plants . 1979, doi : 10.5169 / SEALS-85441 (series of articles in issues 14 and 15).
12. ↑ ^{a b c} Federal Office of Energy (Ed.): Statistics of the hydropower plants . Central sheets ( admin.ch ).
13. ↑ ^{a b c d} Franz Benelli: Oberhasli power plants: Further expansion studies of Oberhasli power plants and effects of the EIA . In: Schweizerische Bauzeitung . tape 105 , no. 39 , 1987, pp. 1131-1137 , doi : 10.5169 / SEALS-76716 .
14. ↑ The history of the Grimsel Association. In: Grimselverein. October 18, 2016, accessed May 24, 2020 . 
15. ↑ Investment for the future. In: Grimselstrom. KWO, accessed on May 22, 2020 (Swiss Standard German). 
16. ↑ KWO (Ed.): Upgrading of the Handeck 2 and Innertkirchen 1 power plants . ( bern.ch [PDF]).
17. ^ Innertkirchen 1. In: Grimselstrom. KWO, accessed on May 22, 2020 (Swiss Standard German). 
18. ↑ Federal Office for Energy (Ed.): Statistics of the hydropower plants . Central sheets ( admin.ch ).
19. ↑ Power plant extensions Innertkirchen 1E and Handeck 2E (tandem). In: RAOnline EDU. 2016, accessed May 22, 2020 . 
20. ↑ Retrofit Power Plant Handeck 3 . In: Grimsel Hydro (Ed.): Profile . No. 1 , 2017, p. 6 ( grimselhydro.ch [PDF]).
21. ↑ Jungfrau Zeitung: "Politics will not let hydropower sink". January 21, 2016, accessed June 6, 2020 . 
22. ^ Power plants: Innertkirchen 3. In: Grimselstrom. KWO, accessed on May 23, 2020 (Swiss Standard German). 
23. ↑ Replacement Spitallamm Dam - The Project. In: Grimselstrom. KWO, accessed on May 23, 2020 (Swiss Standard German). 
24. ↑ Stefan Schmid: Slim replacement building at the moated castle . In: Baublatt . No. 11 , 2019, pp. 12–17 ( baublatt.ch [PDF]).
25. ↑ Jungfrau Zeitung: Despite financial uncertainties, the expansion is still planned. June 23, 2018, accessed June 6, 2020 . 
26. ↑ Handeckfluh power plant. In: Grimselstrom. KWO, accessed on June 6, 2020 (Swiss Standard German). 
27. ↑ ^{a b c} KWO (Ed.): New construction of the reservoir and Trift power plant . Project sheet. ( grimselstrom.ch [PDF]).
28. ↑ Wilfried Haeberli: Glacier Shrinkage: Dangers and Potentials of New Lakes in the High Mountains - Swiss Energy Foundation. Swiss Energy Foundation, accessed on May 24, 2020 . 
29. ↑ Rebecca Holzer: The Trift power plant takes the next hurdle. In: Jungfrau newspaper. April 13, 2020, accessed May 24, 2020 . 
30. ↑ Grimsel 1E power plant. In: Grimselstrom. KWO, accessed on June 6, 2020 (Swiss Standard German). 
31. ^ Jungfrau Zeitung: Grand Council Commission for Grimsel 1E. August 18, 2014, accessed June 6, 2020 . 
32. ↑ Stefan Schmid: Challenging replacement construction of the dam wall on the Grimsel. In: Baublatt. November 8, 2019, accessed on June 6, 2020 (section Further expansion steps ). 
33. ↑ Grimsel pump storage plant 3. In: Grimselstrom. KWO, accessed on June 6, 2020 (Swiss Standard German). 
34. ↑ Jungfrau Zeitung: KWO suspends Grimsel March 3 , 2013, accessed on June 6, 2020 . 
35. ↑ Enlargement of the Grimselsee. In: Grimselstrom. KWO, accessed on June 6, 2020 (Swiss Standard German). 
36. ↑ Helmut Stalder: Raising the dam wall on the Grimsel becomes a touchstone for the energy transition . In: Neue Zürcher Zeitung . ( nzz.ch [accessed June 6, 2020]).
37. ↑ Expansion project. In: grimselstrom.ch. KWO, accessed on May 13, 2020 . 
38. ↑ ^{a b c d} KWO Kraftwerke accessed on July 26, 2020
39. ↑ ^{a b c} Annual Report 2019 , accessed July 26, 2020
40. ↑ Expansion project. In: grimselstrom.ch. Oberhasli power plants, accessed on May 13, 2020 . 
41. ↑ Rebecca Holzer: The Trift power plant takes the next hurdle. In: Jungfrau newspaper. April 13, 2020, accessed May 13, 2020 . 
42. ↑ Helmut Stalder: Raising the dam wall on the Grimsel becomes a touchstone for the energy transition. In: NZZ. June 27, 2019, accessed May 13, 2020 . 
43. ↑ The expansion of hydropower in the Gental and Gadmental with the Fuhren power station . In: Schweizerische Bauzeitung . tape 79 , no. 44 , November 2, 1961, pp. 755 , doi : 10.5169 / seals-65615 .

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