Following a vote on 28 April new emissions levels deemed achievable by best available technology, which will come to underpin power plant permitting within the EU, were agreed at a meeting of EU member states and the Commission. This marked the culmination of about six years of negotiations. The next steps are translation of the new requirements into the official languages of the EU and publication in the Official Journal of the European Union, expected in the fourth quarter of 2017 or early 2018. Publication in the OJEU will trigger a four year long compliance period, at the end of which all power plant permit conditions must have been updated to reflect the new standards and all installations must comply with the new permit conditions.
The new requirements, the Large Combustion Plant BREF (BAT reference document) emissions levels, designed to reflect those achievable with BAT (“best available techniques”), are substantially lower than the emissions limits set out in the EU Industrial Emissions Directive, itself representing a considerable tightening of limits relative to the old LCPD regime. Large Combustion Plant means units of over 50 MWt.
A final draft of the LCP BREF was issued in June 2016 and was made available to the so-called ‘IED Article 13 Forum’. Article 13 of the IED requires the European Commission to organise an exchange of information between itself, member states, industry, and non-governmental environmental organisations.
The Article 13 Forum gave its opinion at a meeting on 20 October 2016, paving the way for the 28 April vote. The 28
April vote was taken by the ‘IED Article 75 Committee’ (which consists of representatives of member states and is chaired by the Commission).
The new BREF levels will become the reference for setting permit conditions in Europe (binding, but with scope for derogation in certain circumstances), while the binding emissions limits set out in the IED, will act as a kind of safety net. As well as being more stringent, the new BREF requirements also consider new classes of pollutant, notably mercury (with, eg, levels down to <1-2 μg/Nm3 dry@6%O2 mentioned for new plants), HCl, HF and NH3.
German power plant trade body VGB is unhappy with the new levels, saying that the emissions requirements for NOx at existing lignite fuelled power plants and those for mercury at lignite and hard coal fuelled power plants “go significantly beyond the level of technical and economic feasibility required by the European Directive”. It also says “criticism of how the bandwidths were deduced, which was comprehensively founded on a scientific basis” has not been sufficiently taken into account, even though reservations were clearly made known to those responsible for drawing up the new levels, and were highlighted during the review process. “The emission bandwidths stipulated are therefore considerably too low”, says VGB, which regrets that “the objectively necessary and technically and commercially justified corrections have not been made.”
It also notes that the German government has requested corrections with regard to nitrogen oxides at existing
lignite fuelled power plants.
“We are now relying on a certain amount
of discretion in the implementation of the new EU requirements in national law, so as to avoid premature closure of power stations as a result of inappropriate emission requirements. The national implementation should be oriented towards the upper emission bandwidths, above all in the cases of nitrogen oxides and mercury”, VGB argues.
At a recent workshop in South Africa on mercury emissions from coal organised by the IEA Clean Coal Centre, Alfons Kather of Hamburg University of Technology demonstrated how, in his view, the BAT Reference development process for setting mercury emissions ranges had resulted in values for the lower limits which were available for member states to set that would be impossible to meet in existing lignite units. At the same workshop it was pointed out that there is no certified continuous mercury measuring system to cover the 1-2.5 μg/m3 range, and it was unlikely to be available by the time the new BREF standards are adopted.
EPPSA, the European Power Plant Suppliers Association, has taken a much more positive stance and welcomed the outcome of the 28 April vote and conveyed its congratulations to the European Commission, the representatives of the member states and the industry in achieving this result, describing it as “an important step in the right direction”.
EPPSA noted that during the negotiations it had “supported the integration of minimum efficiency requirements for the retrofit of the least efficient plants and shared information
on European state-of-the-art technologies on flue gas cleaning and generation technologies”.
It is also “fully aware that some existing power plants in Europe will find it challenging to reach all the defined emission levels”, with the possibility that their economic viability is endangered. In such cases, “exceptions from the IED may apply” (as set out in Article 15.4).
Nevertheless, EPPSA believes that for most of the existing Large Combustion Plants, implementation of the new standards is “economically and technically feasible through the state-of-
the-art technologies currently available in the market”, pointing to examples of flue gas cleaning and mercury removal technologies mentioned on its website.
In the case of mercury EPPSA notes that every control technology basically uses an oxidation stage and a separation stage, with some processes requiring an additional treatment process.
EPPSA presents the table opposite to show how some of the most common already-installed flue gas treatment equipment could be retrofitted to reach mercury removal efficiencies better than 95%. To take into consideration the
influence of fuel type, two different fuel qualities – lignite coal with low halogen content (Cl content < 0.03% in coal) and bituminous with high halogen content (Cl content > 0.1% in coal) are considered. The mercury content in the coal is assumed to be around 0.2 mg/kg.
The oxidation and separation technologies shown in the table are already used in a number of plants worldwide, says EPPSA, while the additional treatment technologies have been demonstrated in large scale applications in the USA and in large scale demonstration projects in Germany.
