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Archive for the category “Germany”

New Approach Pumped Hydro Storage

A company from Stuttgart, Germany proposes a new way of thinking about hydro storage. The design entails a giant cylinder with a stone piston sawn out of rock. During times with excess renewable energy the piston is lifted by water pressure from underneath. The potential energy can be retrieved by letting the piston sink again, propelling turbines.

A first pilot of 30 m deep and 20 m diameter is to be build in Saudi-Arabia, but no financial means have been allocated so far. Paperware so far.

[] – Company site
[] – Tüftler machen Gefällekraftwerk ohne Gefälle möglich


Solar Air Collectors

Early December, outside temperature 6C/43F. Two simple air collectors and ventilators. Max output temperature: 62C/143F

[] – Solar air collector project in northern Germany

Still waiting for the first solar air collector project where the black absorber back plate consists of a black solar panel. The collector should be constructed as such that the glass/acryl cover can be removed in the spring and put back again in the autumn to avoid too high solar panel temperatures during the summer. Special construction absorber with window screen.


Siebdruckplatten: Materialstärke (Seitenwände) 21 mm – 35 €/m²
Materialstärke 9 mm (Rückwand) – 20 €/m²
Acryllack, Dose mit 125 ml – 4,99 €
Aluschiene, 1 cm x 3 cm x 200 cm (2mm), 2 Stück –
Aluschiene, 3 cm x 3 cm x 200 cm (2mm), 1 Stück –
Aluschiene, H – Form
Schrauben V2A, 4 x 25
Schrauben V2A, 3,5 x 16
Schrauben V2A, 4,5 x 45
Fiberglasnetz, 1m x 3,40 m
Acrylglasscheibe (Gewächshaus) 70 x 160 cm
Computerlüfter 12 V, 120 mm, 115 m³/h

Acryl cover

The end result

Some data:

01.03.2013 – complete sunny day
Collector temperature: 39,5 °C

VW E-Crafter Van 200 KM Range

First roll-out in Germany, Holland, UK, Sweden.

[] – Volkswagen Delivers First e-Crafter Vans To Customers In Europe

Siemens Reports EROI Onshore Wind of 50 or Larger

Siemens SWT-3.2-113

According to the manufacturer Siemens has their SWT-3.0-113 wind turbine an energy payback time of 4.5 months. With a (conservative) minimum life span of 20 years, that would mean an EROI of 240/4.5 = 53.

[] – Press release

High Temperature Electrolysis

Sunfire’s field of operation

Dr. Oliver Born: this presentation is mainly about using waste heat steam for hydrogen production. With steam you can typically achieve 20% higher efficiency with steam than with low temperature water.

[] – High-temperature electrolysis

During electrolysis, the amount of electrical energy that must be added equals the change in Gibbs free energy of the reaction plus the losses in the system. The losses can (theoretically) be arbitrarily close to zero, so the maximum thermodynamic efficiency of any electrochemical process equals 100%. In practice, the efficiency is given by electrical work achieved divided by the Gibbs free energy change of the reaction.

In most cases, such as room temperature water electrolysis, the electric input is larger than the enthalpy change of the reaction, so some energy is released as waste heat. In the case of electrolysis of steam into hydrogen and oxygen at high temperature, the opposite is true. Heat is absorbed from the surroundings, and the heating value of the produced hydrogen is higher than the electric input. In this case the efficiency relative to electric energy input can be said to be greater than 100%.

[] – Sunfire company site

[] – Low cost hydrogen production
Sunfire achieves 82% electrolysis efficiency in their hydrogen generator modules.
Input: saturated steam 40 kg/h @ 150°C and pressure: 3 bar(g)

British contribution: scaling up electrolysis to 100 MW

Bauablauf GeoCollect-Erdwärme-Absorber-System

[] – Company site
[] – Preisliste
[] – Effizienter Erdwärmekollektor mit geringem Platzbedarf

Hamburg Tests Thermal Storage of WindPower

The thermal store for wind energy, which is being developed in Hamburg, is a joint project between Siemens, Hamburg Energie and TUHH. The German Federal Ministry for Economic Affairs and Energy is funding the project.

Siemens-Gamesa will build a thermal energy storage of 1000 tonnes of rock fill, that at 600 degrees Celsius will provide 30 MWh electricity. This is the equivalent of the batteries of 50 e-vehicles.

[] – Start of construction in Hamburg-Altenwerder: Siemens Gamesa to install FES heat-storage for wind energy

Nordex Awarded 180-MW Project in the Netherlands

Location: Wieringermeer, 60 km north of Amsterdam.
Substance: 50 N117/3600 turbines

[] – Nordex Awarded 180-MW Project in the Netherlands
[] – Nordex SA

Read more…

Vattenfall Orders 1 GW Wind Park from Siemens-gamesh

The largest offshore wind order of 2017: the three wind farms, Kriegers Flak in the Baltic Sea and Vesterhav Syd and Nord in the North Sea, have a total investment value of close to EUR 1.7 billion (SEK 16.5 billion).

[] – Vattenfall Places Historically Large Wind Power Order
[] – Vesterhav Nord/Syd Offshore Wind Farm
[] – Vattenfall Inks Danish Offshore Wind Contracts

Siemens, Airbus and Rolls Royce Aim at Hybrid Electric Plane by 2020

[] – Siemens, Airbus, Rolls-Royce team up on hybrid-electric propulsion

Hans-Josef Fell – Das Tempo der Energiewende

German language video.

Hans-Josef Fell is one of the most important advocats of renewable energy in Germany. He was the man behind “feed-in tariffs”, introduced in Germany in 2000 and and set an example for the rest of the world.

Fell has bad news: the energy transition in Germany is stalling. Were in 2000, 7 GW of new capacity was installed, in the last few years it has fallen back to 1.5 GW. Big oil, coal and lignite producers are successful in slowing down the transition.

[] – Hans-Josef Fell

New Car Mileage and Emission Certification Test WLTP


Most people realize that official mileage data from car manufacturers are bogus. On average their figures are 42% better than reality as established by the International Council on Clean Transportation (ICCT). The ICCT was one of the clubs that helped unveiling the VW diesel scandal. One of the main reasons behind the discrepancy is the 1992 old test method called NEFZ (“Neuer Europäischer Fahrzyklus” or “New European Driving Cycle”).

Meanwhile there is new test method WLTP (“Worldwide Harmonized Light Vehicles Test Procedure”) that should shorten the distance between test and reality. WLTP is in force since September 1, 2017 for new cars

[] – Die Verbrauchslüge

World’s Largest Windturbine Nears Completion

Note water reservoir at the bottom of the tower.

Location: Gaildorf, Baden-Wuertenberg, Germany
Hub height: 178 m
Total height: 246 m
Investment: $81 M
Yearly return: $7.6 M
Annual production: 10.5 GWh
Payback time: 10.6 year

Apart from these impressive figures, the turbine has an innovation in the form of a “natural storage” facility. At the bottom of the tower, the turbine has a water reservoir of 40,000 m3 that communicates with a lake reservoir at 200 m lower altitude and connected with a 5 km long pipe. This reservoir represents a potential energy of 22.2 MWh or five hours worth of max. windturbine output. Energy efficiency: 80%.

[] – Max Bögl Wind puts turbine on THE tallest tower
[] – Naturstromspeicher Gaildorf
[] – The Naturstromspeicher – Our Big Green Battery
[] – ’s Werelds hoogste windmolen staat in een piepklein stuwmeer


German Grid Still Reliable Despite Growing Renewable Energy

Despite a growing share of renewable energy in Germany, the grid remains as stable as ever: the average German has on average to endure a 11.5 minute/year blackout. Although grid stability will become an increasing challenge, for the moment everything is still fine.

[] – Duitse stroomnet ondanks pieken windenergie superbetrouwbaar

Self-Heating Building with Algae

Renewable energy is generally associated with windturbines and solar panels. It is often ignored that electricity is only part of the entire energy story. In northern Europe for instance an average household needs to pay more for space heating than for electricity on a yearly basis. The BIQ building in Hamburg could provide the solution for an energy-neutral home that collects solar energy all year around and stores part of the solar energy in the form of algae. The algae biomass can be used for gas production and is easier and cheaper to store than warm water. Up-front capital costs are high though: $2500/m2. Reduction on fossil fuel cost to date is 33%. This number could increase if solar panels are placed on the roof, used to produce electricity to power heat pumps.

[] – This Algae-Powered Building Actually Works (2014)
[] – Tomorrow’s architecture, starring algae and hemp (2016)

Hans-Josef Fell – Accelerating the Global Transition to 100% Renewable Energy by 2030

[source] Hans-Josef Fell

One of the main proponents behind the Energiewende in Germany is Hans-Josef Fell. Now he has written an article with a proposal how to speed up the global energy transition towards 100% renewable energy, enabled by the recent spectacular price declines. Fell says that 2030 should be possible. “80% energy from the region for the region” is the key to success in achieving 100% renewable energy.

Full story below:

[] – Accelerating the global transition to 100% renewable energy
[] – Hans-Josef Fell

Evaluation 12 out of 36 Power-to-Gas Projects in Germany

Short German study regarding an inventory of power-to-gas projects, see map. Currently in Germany there are 36 PtG projects operational and 12 of those were highlighted, all demonstration projects. Start date projects 2010-2017. Power range 0.15 MW bis 6.3 MW. 9 projects are about hydrogen production, in 2 projects produced hydrogen is converted into methane. Reported efficiencies: 65-80% which includes heat utilization.

Potential PtG in transport, heat, electricity storage and system integration

Most potential in systems integration and transport. Efficiency increases hydrogen production until 2030 are estimated as between 5-10%. Potential cost decrease until 2030: 30-70%. The majority of respondents expect PtG to be competitive with natural gas between 2020-2040 and of those a majority between 2020-2030.

[] – Praxis und Potenzial von Power-to-Gas (pdf)
[deepresource] – Power to Gas

Hey Taxi! – Volocopter Maiden Flight

Autonomous air taxi takes off in Dubai. German development.

[] – Volocopter
[] – Lufttaxi meistert Jungfernflug über Dubai

Read more…

Blueprint 100% Renewable Energy Base for Germany

Hans-Martin Henning and Andreas Palzer of the Fraunhofer Institute for Solar Energy Systems in Germany have set up a computer model for a 100% renewable energy base for Germany and have used that model to find the most cost effective configuration. The result can be seen in the diagram.

The energy inputs are:

Source Power [GW] Annual energy [TWh]
Solar panels 252 246
Onshore wind 200 360
Offshore wind 85 297
Hydro-power 5 21
Electricity import 0 0

Scale the numbers up and you have the solution for Europe, with significant changes in numbers for individual nations. The cost of this renewable energy system would not be higher than our current fossil fuel based energy system.


Gud – “Gas und Dampf” (gas and steam).
KWK – “Kraftwärmekopplung” (co-generation. “power-heat-coupling”)
Solarthermie – thermal solar (solar collectors)
BHKW – “Blockheizkraftwerke” (co-generation. “block heat and power generation”)
Gas-Wärmepumpen – Gas-heatpumps
Pumpspeicher – Pumped hydro
Wärmespeicher – heat storage (water medium)
Wärmelast – heat load
WP – “Wärmepump” (heat pump)

[] – 100 % Erneuerbare Energien fuer Strom und Waerme in Deutschland
[] – 27 slides talk Dr. Hans-Martin Henning
[] – 66 slides talk Dr. Hans-Martin Henning
[] – Deutsche Energiewende klappt nur mit intensiver Wärmedämmung
[] – Two Directors Take Over as Head of Fraunhofer ISE

[] – Sichere Stromversorgung mit 100 % Erneuerbaren Energien ist möglich

[deepresource] – Norway Europe’s Green Battery
[deepresource] – Norway Wants to Become Europe’s Battery Pack
[deepresource] – The European Supergrid
[deepresource] – First Climate Neutral Power Station in The Netherlands
[deepresource] – Opel Ampera E (Chevrolet Bolt)
[deepresource] – Gold Mine North Sea
[deepresource] – Power to Gas
[deepresource] – MERITS Seasonal Heat Storage Breakthrough
[deepresource] – Hamburg Considers Large Scale Storage of Heat

Read more…

Can Society Run on Renewable Energy Alone?

Kris de Decker

The Flamish energy thinker Kris De Decker blogs at “Low Tech Magazine“, was guest author at “The Oil Drum” and writes for many prominent newspapers in Belgium, the Netherlands and the UK. De Decker presents a big picture view on the possibility of a 100% renewable energy society. De Decker preaches “low tech” if not “no tech”.

The article:

[] – How (Not) to Run a Modern Society on Solar and Wind Power Alone

The author admits that there is potentially more than enough renewable energy available. In Europe 10 times, in the US even 100 times present day electricity consumption, that’s not the problem. The real issue is intermittency. How can we guarantee that our energy grids remain stable, like they have been over the past hundred year, when we switch from fossil fuel to renewable energy? They author describes the intermittency of wind and solar in more detail and we assume he has done his homework. A first positive observation is that throughout the year solar and wind intermittency somewhat compensate each other. There is more wind in the winter months and more solar in the summer.

De Decker lists five strategies to combat the negative consequences of intermittency:

  • 1. Backup Power Plants. Don’t opt for 100% renewable energy supply but keep fossil fuel backup capacity alive. And since it regularly happens that no renewable energy is available at all, this would imply that all fossil fuel power generating capacity must remain in place. The only difference is with the present is that they will be (partially) idle for a long time. Essentially a hybrid system.
  • 2. Oversizing Renewable Power Production. “Solution”: build so much capacity that supply always matches demand. The author admits that this would lower the energy efficiency (EROI) because the energy system would over supply which necessitates switching power generation off.
  • 3. Supergrids. Another more practical way to combat intermittency is connecting large geographical areas into a single supergrid and use “statistics” to even out irregular supply. This would require a continental grid with much higher voltages and in Europe a renewed grid with twelve times more transport capacity.
  • 4. Energy Storage. The author claims that in the case of Europe, 400 TWh net storage capacity is needed or 1.5 months worth of consumption. Pumped hydro can supply 80 TWh and car batteries 7.5 TWh. The rest should be batteries.
  • 5. Adjusting Demand to Supply. The author (correctly) questions the necessity of “supply should always meet demand”. Why not consume energy if it is available. The Dutch of the 17th century for instance reclaimed new land by pumping it dry and sawed planks for their commercial fleet with wind power, despite its intermittency.

There is not much wrong with the article and De Decker basically supports the idea of a 100% renewable society even if he is skeptical that we can have a plug-and-play solution and instead advocates that we should learn to live with a less comfortable situation where demand will follow supply instead of the other way around.

Is he right? Eh no. He is ignoring the impact of other promising storage technologies. Take the blueprint of the 100%-renewable energy model as promoted by the renowned German Fraunhofer Institute. Note this is the overall energy picture, not just electricity. The model and numbers are for Germany, but can be scaled up for Europe, with adaptions in the numbers for the respective local situations:

[source] 100% renewable energy blueprint for Germany according to the Fraunhofer Institute

Summary in numbers:

Input: 542 GW intermittent renewable energy, mostly wind (200 GW) and solar (252 GW).

Storage: batteries 52 GWh, pumped hydro 60 GWh, power-to-gas (methane) 88 GW and other, see legenda:

Gud – “Gas und Dampf” (gas and steam).
KWK – “Kraftwärmekopplung” (co-generation. “power-heat-coupling”)
Solarthermie – thermal solar (solar collectors)
BHKW – “Blockheizkraftwerke” (co-generation. “block heat and power generation”)
Gas-Wärmepumpen – Gas-heatpumps
Pumpspeicher – Pumped storage (hydro)
Wärmespeicher – heat storage (water medium)
Wärmelast – heat load
WP – “Wärmepump” (heat pump)
Überschuss Wärme – Excess heat

Essential is the Energiesanierung (energy renovation) of buildings, which should result in a reduction of space heating energy requirement of 64.9% as compared to 2010 level.
According to the Fraunhofer Institute would the cost of this renewable energy system not be higher than our current fossil fuel based energy system.

[] – Kris de Decker
[] – 100 % Erneuerbare Energien fuer Strom und Waerme in Deutschland
[] – Wie Deutschland auf 100 Prozent Ökostrom umsteigen kann
[] – Stabilität im Zeitalter der erneuerbaren Energien

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