Saturday, October 17, 2015

Cogeneration – highly efficient or overestimated technology? – Energy Consumer Portal

                 In addition to the expected increase in the EEG apportionment come to 2016 additional extra cost of 10 euros for the cogeneration premium to the average German household. Cogeneration is not one of the renewables, but it is considered an important bridging technology until full implementation of the energy transition.

“Highly efficient” use of resources

The abbreviation CHP puts the simultaneous production of electricity and heat. The realized in cogeneration technology will account for around 25 percent of electricity generation by 2020 according to the will of the federal government. Background is the lack of use of up to 60% of the fuel energy in fossil fuel power plants. In the combined heat and power generation, the efficiency of fuel increased considerably, for example by the produced during the water heating via steam turbine generates electricity. The efficiency of the fuel used is thus higher by up to 50% and provides through reduced CO2 emissions a major contribution to climate protection. At the same time saving operators of CHP systems 30 to 40% of their energy costs. 2010, the CHP share of electricity was in the industry at 62%. Also swimming pools, hospitals and large residential complexes use it more and more.

The federal government has now decided to double the amount of CHP apportionment. Meanwhile, offer almost all well-known manufacturers heating mini Heizblockkraftwerke to the size of a refrigerator, which should allow in smaller residential units the use of technology. While many assess the increased funding as a positive signal for the required expansion of technology, there are also a number of skeptics who hold the potential of cogeneration for overrated.

skeptics doubt the potential for cogeneration

Gerhard Luther, co-author of “Energy Study 2014″ the German Physical Society (DPG) even speaks of “cogeneration Myth”: The positive characteristics of the CHP would benefit from the political and public “quite exaggerated,” the however, negative properties largely ignored. In fact, studies in very different results. While partially attest the CHP “high-efficiency” and a big savings, yield different research results only minimally better results compared to the solution with separate conditioning systems. According to Luther from the widely quoted primary energy savings of up to 50 percent in cogeneration solutions could be no question. For calculations only the control mode is taken into account and remember that would be added during peak load periods separate boilers or electricity volumes to meet demand.

Most of cogeneration are heat out. If heat is needed, jump to the plants and simultaneously produce electricity, which consumes either directly or can be temporarily stored in small power saving. Excess electricity can also be fed into the grid and bring a bonus by the feed-in tariff. Although there are also thermal storage, most CHP plants are equipped only for the basic heat demand, but not for peak heat output of some winter days.

Doubtful balance of micro-power stations

Although there are increasingly small systems for single and two-family houses, the profitability of micro power plants compared to their larger peers is significantly reduced. Not only purchase but also maintenance costs exceed the investment for conventional boilers significantly. As a guideline for a worthwhile purchase

applies an operating period 3500-5000 hours. A study by the Environment Ministry therefore concludes that micro-plants with an electrical output of up to 1000 watts “also with the promotion by the CHP Law does not operate economically “were. “These plants produce significantly higher total annual cost in comparison with a natural gas-fired furnaces.” Larger cogeneration plants with an electrical output of up to 50 kilowatts were however to operate consistently economical considering the CHP surcharges with a return on assets of 5.5 percent.

Federal Government increased funding on

Now the annual funding is raised at the expense of taxpayers and electricity customers by 750 million to 1.5 billion euros, but criticizes Werner Neumann from BUND that before especially smaller CHP plants would not sufficiently promoted. In particular, the exposed promotion of own electricity use of CHP and instead introduced burden of the EEG apportionment encounter little enthusiasm. “What is being sold here as CHP support, is ultimately a barrier to CHP development.”

The proposed development objective is already barely reach. 2013 the share of CHP with a net electricity of 96.4 terawatt hours only 16 percent. Nevertheless, a balance is encouraging. The CHP saves already compared to uncoupled electricity and heat production approximately 56 million tonnes of CO2 a

Certified bridging technology

The Federal Environment Ministry will by 2030 CHP potentials have developed in parallel with the expansion of renewable energies as much as possible. Thereafter, the possible use of hanging “of the structure of electricity generation, the development of electricity demand and the flexibility of the entire power system from”. Finally, cogeneration is despite all the advantages over the conventional electricity and heat only as a bridging technology. Due to their increased efficiency and CO2 savings potential it is still accepted by many eco seals proportionately in the electricity mix

Frankfurter Allgemeine Zeitung
Frankfurter Allgemeine Zeitung


No comments:

Post a Comment