EU Emissions Update

Richard Payne is not only the Customer engineering manager for Cummins G-Drive, but is the exhaust emissions expert for AMPS and Europgen. He has worked closely with the European Commission on the development of the stage V no-road emissions regulation and the Medium Combustion Plant Directive.

Following his delivery on Emissions at the AMPS Conference in March we have reproduced the main body of his powerpoint presentation in the following article.

We are pleased to include 3 related features from AMPS members – Power Electrics, ide systems and Agriemach with their varied approaches on combatting the emissions problem.

Emissions

AGENDA

Stage V non-road mobile machinery
Medium Combustion Plant Directive
UK ‘Specified generator’ legislation
Local legislation

NON-ROAD MOBILE MACHINERY STAGE V

Stage V background

New EU regulation to replace 97/68/EC directive (non road mobile machinery or NRMM directive)
Published in OJEU Sept 2016 as Regulation (EU) 2016/2016
Supplementing legislation published May 2017
Affects mobile generators, primarily rental equipment

Stage V Highlights

<19 CI kW included, aligned with US T4f
>560 kW included, aligned with US T4f
Filter forcing particle number (PN) count from 19-560 kW, not aligned with US T4f
Gaseous fuel, dual fuel, spark ignition and any other type of mobile RICE included, partly aligned with US
Formula to adapt THC limit to allow for Methane slip in gas engines/dual fuel engines (no methane limits in US)
Derogation for ATEX (explosive atmosphere) engine to use stage IIIA limit values.

Limit values – Spark ignition (<56 kW) See Fig 1

NRMM – constant speed ELV’s See Fig 2

Aligns with US <56 kW (apart from note 1).
>56kW all types of engine have the same limit values (see next slides)

NRMM – constant speed ELV’s

DPF forcing from 19-560 kW (due to particle number count)
SCR forcing from 56 kW up (gen-set)
Methane slip limit for gas engines

Transition programs

Flexibility program is completely removed
A limited pre-buy program is allowed

– There are restrictions on how long an engine can be held

before it is installed in a machine and the machine placed on the market

– Extended time line for very small manufacturers

Transition Program

Emissions

MEDIUM COMBUSTION PLANT DIRECTIVE (MCPD)

MCPD Scope

Sets minimum exhaust emission requirements for stationary engines in the EU with a thermal input of 1 MW to 50 MW

– approx. 300 kW to 24 MW mechanical power

It has limits to control emissions of Sulphur dioxide, nitrogen oxides and dust (PM)

– There is also a requirement to monitor Carbon monoxide

It will not prevent national rules that are more stringent;

for example Germany is expected to introduce a new regulation that will be more stringent than this base and have additional substances regulated

Member states must assess the need to apply stricter limits in areas of poor air quality

MCPD Derogations

Plants operating for <500 hours/year may be exempted from the limit values, at the discretion of the member state

– Some averaging allowed
– Should allow exemption of emergency generator from limit values, but not permitting/registration

New engines operating for 500-1500 hour/year may be allowed reduced limits that do not require secondary abatement. In this case the NOx limit is increased to 750 mg (2g TALuft) for high speed diesel engines.
Engines used in the propulsion of a vehicle, ship or aircraft exempt
Research development and testing of MCP exempt

– Member states may apply specific conditions to this

Non-road mobile equipment covered by directive 97/68/EC (replaced by Regulation (EU) 2016.1628 is exempt*
Plant in Canary Islands, French Overseas Departments, the Azores and Madeira are exempt, but must set limit values to reduce risks to health
There are a number of other very specific exemptions

* non-road mobile machinery shall mean any mobile machine, transportable industrial equipment or vehicle with or without body work, not intended for the use of passenger- or goods-transport on the road, in which an internal combustion engine as specified in Annex I section 1 is installed.

MCPD application dates

Member states must transpose the directive into national law by 19 December 2017
The application date for new plants is 19th Dec. 2018
The limit values will apply to existing plant from 5-50 MW thermal input from 2025 (registration or permit 1 year before)
The limit values will apply to existing plant from 1-5 MW thermal input from 2030 (registration or permit 1 year before)

Aggregation

New plants >1MW that do or could use a common stack shall be aggregated to determine thermal input when defining requirements (application dates and limits)
A combination of more than 50 MW is included unless covered by chapter III of 2010/75/EU (IED)

Permitting

All plant within scope will require a permit, even if exempt from limit values

– Many facilities that have an emergency generator will not be aware of this
– Should be a simple process for a simple plant

There are record keeping requirements
There are monitoring requirements

Emission limit values (mg/Nm³) for EXISTING engines and gas turbines

Note: corrected to 15% O2

(1) 60 mg/Nm3 in the case of biogas [40 mg new engines].
(2) 130 mg/Nm³ in the case of low calorific gases from coke ovens, and 65 mg/Nm³ in the case of low calorific gases from blast furnaces, in the iron and steel industry.
(3) 1850 mg/Nm³ in the following cases:
(i) for diesel engines the construction of which commenced before 18 May 2006;
(ii) for dual fuel engines in liquid mode.
(4) 250 mg/Nm³ in the case of engines with a rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW.
(5) 250 mg/Nm³ in the case of engines with a rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW; 225 mg/Nm³ in the case of engines with a rated thermal input greater than 5 MW and less than or equal to 20 MW.
(6) 380 mg/Nm³ for dual fuel engines in gas mode.
(7) Emission limit values are only applicable above 70 % load.
(8) 20 mg/Nm3 in the case of plants with a rated thermal input equal to or greater than 1 MW and less than or equal to 20 MW.

Emission limit values (mg/Nm3) for NEW engines and gas turbines

Note: corrected to 15% O2

* Different to existing engines

(1) Until 1 January 2025, 590 mg/Nm³ for diesel engines which are part of SIS or MIS.
(2) 40 mg/Nm3 in the case of biogas [60 mg new engines].
(3) Engines running between 500 and 1 500 hours per year may be exempted from compliance with those emission limit values if they are applying primary measures to limit NOx emissions and meet the emission limit values set out in footnote (4) [Not available to existing engines].
(4) Until 1 January 2025 in SIS and MIS, 1 850 mg/Nm3 for dual fuel engines in liquid mode and 380 mg/Nm3 in gas mode; 1 300 mg/Nm³ for diesel engines with ≤ 1200 rpm with a total rated thermal input less than or equal to 20 MW and 1 850 mg/Nm³ for diesel engines with a total rated thermal input greater than 20 MW; 750 mg/Nm³ for diesel engines with > 1200 rpm.
(5) 225 mg/Nm³ for dual fuel engines in liquid mode.
(6) 225 mg/Nm³ for diesel engines with a total rated thermal input less than or equal to 20 MW with ≤ 1200 rpm.
(7) 190 mg/Nm³ for dual fuel engines in gas mode.
(8) These emission limit values are only applicable above 70 % load.
(9) Until 1 January 2025, 550 mg/Nm³ for plants which are part of SIS or MIS.
(10) Until 1 January 2025, 75 mg/Nm³ for diesel engines which are part of SIS or MIS.
(11) 20 mg/Nm3 in the case of plants with a total rated thermal input equal to or greater than 1 MW and less than or equal to 5 MW.

ENGINE TECHNOLOGY NEEDED…

Diesel Engine

SCR required to meet NOx limit

– Retrofit of SCR is possible
– Mobile equipment SCR will use up considerable exhaust restriction allowance making exhaust heat recovery more challenging
– Larger SCRs can be used on base load stationary plant leaving more capability for heat recovery

SO2 needs < 2000 ppm fuel for other than gas oil
Modern high speed low emissions engine can meet dust limit

– Older existing engines or large medium/low speed engines may not and additionally need a particle reduction system

Stage V non-road mobile engine will easily meet limits

– Stage IIIA non-road mobile (current) will probably not

Stoichiometric (rich burn) Gas Engine

Three way catalyst (TWC) will be required to meet NOx limit

– This also effectively manages CO and unburned hydrocarbon emissions
– It is a no-maintenance item requiring no additional fluids
– Some exhaust restriction is used by the catalyst but with careful design exhaust gas heat recovery is viable
– It is very important that the air/fuel ratio is tightly controlled around lambda 1 requiring electronic feed back control

Retrofit of a (TWC) is possible but the engine would need to either already have or be retrofitted with such a control system

Lean Burn Gas Engine (premixed)

A low emission lean burn engine can meet the existing engine limits if designed to do so

– Many are since it is the same as TALuft

A lean burn engine can be designed and tuned to meet the new engine limits (1/2 current TALuft) without SCR

– This requires leaner running
– There is a slight loss of specific fuel consumption and flexibility of the engine
– The exhaust temperature is slightly lower but with a higher flow rate giving lower grade but more heat from exhaust heat recovery systems
– System will be sensitive to gas quality

SCR can be added to give very low NOx emissions if a memberstate introduces lower limits

Lean Burn Gas Engine (high pressure gas injection)

These engines have similar combustion to a diesel engine
SCR will be required to meet the NOx limit

UK SPECIFIED GENERATOR LEGISLATION

Background

The UK has seen a rapid rise in the number of, and operating hours of, diesel gen-sets in response to demand created by the ‘balancing services’ market
Many of these gen-set are of older design vintage
There is concern for local air quality and using up NEC directive NOx allowance
Additional controls over and above the MCPD are being applied to ‘specified generators’
MCPD requirements also apply (however, many of these generators would fall out of MCPD emission limit values due to low hours)

Included generators

Any generator or group of generators (not excluded) from 1 – 50 MWth
Any generator or group of generators (not excluded) providing balancing services <50 MWth (no lower limit)
A group of generators are considered a generator if:

– on the same site, and;
– operated by the same operator, and;
– for the same purpose

Excluded from ‘specified generators’

Back-up (stand-by) generators operated for the purpose of testing for no more than 50 hours per year. Cannot have any other function.
Back-up (stand-by) generator that has demonstrated a genuine need to test for more than 50 hours per year (needs special approval confirming no air quality exceedance)
Mobile generator unless connected to

– an electricity transmission system or distribution system, or;
– other apparatus, equipment or appliances at a site, and is performing a function that could be performed by a generator that is not mobile;

Generator used at a site which it is not reasonably practicable to connect to the distribution system (needs special approval confirming no air quality exceedance)
Generators subject to the IED (chapter II or III)
Generators operating with a defined nuclear safety role
Generators installed on an offshore platforms or on a gas storage or unloading platform

Tranche A generator

Tranche A generators are subject to transition arrangements
The principle behind a Tranche A generator (or group of generators) is that the operator could not reasonably have foreseen the emissions regulation when putting the plant into operation or entering into a balancing services contract
The inclusion of generators of less than one megawatt was at a later date and therefore a slightly different definition and timings

Tranche B generator

A tranche B generator is any other generator (other than an excluded generator) or a tranche A generator that has lost its entitlement to be tranche A
A Tranche B generator must fully meet the emission and administrative requirements of a ‘specified generator’

Tranche B generator

A tranche B generator is any other generator (other than an excluded generator) or a tranche A generator that has lost its entitlement to be tranche A
A Tranche B generator must fully meet the emission and administrative requirements of a ‘specified generator’

Emission Limit Values