Diesel & gas engines |
Optimising gensets to reduce emissions
Diesel gensets are reliable and flexible workhorses, with low cost of ownership. But their emissions must be reduced. The good news is that a number of options are available, conversion to HVO fuel being one of them, which do not noticeably reduce performance or increase costs
Nicole Dierksheide Director of Large Engine Power Systems, Kohler
Diesel gensets are relied upon to provide emergency backup in a broad range of applications. They offer reliability and high performance, starting up quickly, in 10 seconds or less, to provide a guaranteed source of electricity when needed.
Diesel generators also offer a low total cost of ownership. The latest designs have been optimised for fuel efficiency and reduced maintenance needs. They are supported by a well-established fuel supply infrastructure to underpin continuity of operation.
So, diesel gensets are seen as workhorses. But there is a challenge. The climate crisis means that all organisations are under significant pressure to comply with environmental regulations and to achieve corporate sustainability goals. Anything that uses fossil fuels will, rightly, be subject to increased scrutiny, to see how its emissions can be reduced.
Diesel generators are in this category. So how can their emissions be minimised to reduce environmental impact while maintaining resilient power supply?
Critical factors for generator deployment
The first consideration when selecting a genset is to understand its application fully. It might be covering power outages and planned maintenance, managing grid instability and meeting peak
demand. It could also be used to support the integration of renewables, and other applications. Once the application for the generator has been understood, and the requirements for how much power is needed, a good next step is to review regional regulations.
For the USA, installations are regulated by the EPA. The EPA Tier 4* requirements have made good progress in reducing emissions, and pockets of specific air quality management districts (AQMD) with stricter regulations are also emerging. This includes California, Virginia, and other areas of the east coast. It’s key to understand those local regulations and pick a technology that will meet the specific requirements in that area.
In the EU, there are similar requirements for emissions, including Stage V. The MCPD (Medium Combustion Plant Directive)** aims to reduce harmful emissions such as NOx from gensets and other mid-size equipment (rated between 1 MWt and 50 MWt). The directive is adapted (transposed) to each individual country. Another important factor is that operators simply want to be better. They want to provide the greenest solution or use the best available technology, and go beyond what the legislation demands, for example by adding an additional after-treatment system to their genset. Once the role of the genset has been fully analysed and the applicable environmental
legislation fully assessed, viable options for reducing emissions, if required, can be reviewed. Let’s look at a few technologies that can help.
HVO: a renewable fuel One of the biggest opportunities to reduce generator emissions is by switching from fossil diesel to renewable fuel. In particular, hydrotreated vegetable oil (HVO) can provide an effective alternative to diesel, which can help reduce overall greenhouse gas emissions. HVO is usually made by the hydrogenation of vegetable oil, or by hydrocracking. Also known as green diesel or renewable diesel, using HVO
instead of conventional diesel reduces net CO2 emissions by up to 90%.
Since HVO is similar in grade and quality to conventional diesel, it can be used without modification of infrastructure, or any need to buy new engines. It is compatible with the standard mix of petroleum-derived diesel fuels, so it can also be blended with fossil diesel – thus increasing flexibility for the end-user. It is easy to store and handle and can be kept for years without major degradation.
HVO is made from waste products and residues that don’t impact agricultural land use, including vegetable oils, animal fats, and used cooking oils. It could also be made from photosynthetic organisms such as algae in the near-to-medium term.
*
https://www.epa.gov/regulations-emissions-vehicles-and-engines/regulations-emissions-heavy-equipment-compression **
https://environment.ec.europa.eu/topics/industrial-emissions-and-safety/medium-combustion-plant-directive_en
38 | November/December 2023|
www.modernpowersystems.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55
