Within three decades, the aim is for almost the entire energy supply in the Netherlands to be sustainable. No fossil fuels. No (Groningen) natural gas. Gasless. Gasless? Gas does appear to be necessary for an efficient and feasible energy transition. Sustainable gas. The positive properties of this energy source at a glance.
Energy source – Biogas is an energy source that does not require conversion to obtain the energy, making the efficiency high. Hydrogen, for example, is an energy carrier; it is produced through conversion (with conversion loss) of natural gas or electricity (the energy source).
Hydrogen - Currently, >90% of hydrogen is produced by steam reforming: with an efficiency of approximately 75%, hydrogen and carbon dioxide are made from natural gas and water. This is called gray hydrogen through the use of fossil natural gas.
More and more initiatives are being developed for the production of green hydrogen. Electrolysis is a technique in which electricity is used for hydrogen production with an efficiency of approximately 75%. In the long term (>10 years) this route offers many opportunities. For example, for storing or transporting local excess production of electricity. Conversion of electricity from large solar parks into hydrogen for use on another continent is an example of this. In terms of application, I believe hydrogen will be particularly interesting for industry in the future (see further in this blog).
Residual flows – Biogas is produced from inexhaustible organic residual flows via anaerobic fermentation. These residual flows are available in abundance regionally. Consider manure, organic waste, waste from the food industry, sludge flows from water purification or agricultural residual flows.
Did you know, for example, that no less than 1,5 billion Nm3 (cubic meters) of green gas can be produced from all available manure in the Netherlands? With an average annual gas consumption of 1.350 Nm3, this means more than 1 million warm Dutch homes!
Applications –Biogas is a sustainable energy source for various flexible applications:
- Green gas production from biogas. Biogas has a low methane content (50-65%). Thanks to biogas upgrading, such as with membrane technology, it is brought to the right quality with the same properties as natural gas. Any desired gas quality and calorific value is possible and can be fed into both the low and high pressure natural gas network.
- Bio-CNG or bio-LNG from biogas. A sustainable fuel for vehicles. Bio-CNG production is also ideal if there is no gas infrastructure at the biogas production location. HoSt already has several of these in America 'virtual pipeline' systems supplied. The production of LNG is slightly more complex, but LNG has approximately 3 times the energy content of CNG;
- In a combined heat and power plant (bio-CHP), biogas can be converted into heat and green energy;
- Direct use in industry, by burning biogas on biogas boilers for process heating.
Flexibility - One of the main advantages of biogas is its year-round production. Solar and wind energy have limited full load hours, which causes peak loads on the grid and requires smart storage methods for the future. The gas network acts as a buffer when the demand for gas is lower. This means that not a cubic meter of gas is wasted and biogas can play an important role in balancing the energy supply.
Infrastructure – The Netherlands is the most populous country in the European Union (EU). The Dutch gas infrastructure has exceptionally good national coverage. And a central heating boiler that can run on green gas without adjustments is available in almost all Dutch homes and buildings. The gas network can also be used for the transport of hydrogen, but adjustments are required because hydrogen can easily escape from valves and valves because it is a light gas. Green gas has a three times higher energy density (approximately 3 Kwh/Nm9) compared to hydrogen and adjustments to the grid are not necessary.
Millions of homes are difficult to get rid of gas (affordably), because low temperature heating, which is required for electric heating with a heat pump, is not feasible or affordable. It is not without reason that it is expected that by 2050 between 40% and 60% of our energy will still have to come from gaseous energy carriers.
Achieving the sustainable energy ambitions requires a combination of gas-free construction, adapting existing homes to heating with heat pumps and green gas for really old homes.
Mobility – My expectation is that most of the transport will eventually become electric. Green gas will have a share in the energy mix for transport through CNG and LNG, which is particularly interesting for heavy duty transport (ships/trucks). With the exception of heavy duty transport, hydrogen is not interesting for mobility, as too much energy is lost in both production (approximately 20-30%) and in the fuel cell (approximately 40%). Furthermore, CNG and LNG also suffer from a loss of efficiency in the combustion engine.
Emission reduction – The central government is encouraging the energy transition, but also CO2 emission reduction techniques. Green gas production from sustainable low-quality regional bio raw materials delivers an emission reduction of no less than 90% compared to the use of natural gas. In addition, fermentation in combination with green gas production ensures an additional emission reduction; after all, emissions from residual flows are reduced. As an example: manure fermentation reduces nitrogen and methane emissions by approximately 40% and 60% respectively. The methane is usefully used for the production of biogas, so it is not released into the atmosphere. Two birds with one stone.
Biogas production is a readily available clean technology and green gas is necessary for a realistic energy transition in the Netherlands. Focusing on a combination of gas-free new construction, adaptation of existing buildings to heating with heat pumps and green gas for old homes seems to be the right route. Time to give (green) gas!
