Recently, we have highlighted several of the latest court rulings such as in different ways, categorically accustomed to the car manufacturers who have been behind the diesel emission scandals. These judgments have references to technical topics such as NOx emissions, EGR valves, and not least thermal window, soå so that we can understand judgments better, and not least what they mean for our appeals, our environment and our health, let's take a look at what these "things" revolves around.

We start with the end, with NOx, i.e. part of the exhaust.

How is NOx formed in diesel engines?

NOx stands for nitrogen oxides, usually used as a collective term for nitrogen monoxide (NO) and nitrogen dioxide (NO2). NO is a colorless and odorless gas, while NO2 is reddish brown and has a pungent smell.

High combustion temperature and pressure in the engine cause nitrogen (N2) in the air to react with oxygen (O2) and form NO and NO2, especially at high temperatures in the combustion chambers. Diesel engines normally operate with excess air and high thermal efficiency, conditions that increase the likelihood of NOx formation compared to many petrol engines. 

In other words, diesel engines are more efficient, they get more "power" out of the fuel than a petrol engine, but with that it also follows; a disadvantage, namely that diesel engines produce more harmful emissions. What we colloquially call "the cylinders" in the engine is referred to here as "combustion chambers", i.e. where fuel and air are mixed and burned, which produces power and exhaust gases.

At high loads, e.g. a heavily loaded car, at high speed or strong acceleration, causes NOx emissions. High combustion temperature in the engine itself also The NOx emissions, and modern diesel engines therefore have systems that lower, or can lower, the combustion temperature. One of these is the EGR system, which we will see in more detail below. in the next article.

Why NOx is harmful to health

In the course of the last couple of decades, it has become increasingly clear that «production», i.e. emissions, of NOx is absolutely nothing å seek after:

• Irritation and respiratory disease: NO2 irritates the respiratory tract and can both cause and worsen asthma and contribute to the development or worsening of chronic respiratory diseases.
• Cardiovascular diseases: Long-term exposure to particles and NOx is linked to an increased risk of cardiovascular diseases.
• Cancer: A connection between diesel exhaust and cancer has been proven. The World Health Organization has classified diesel exhaust / nitrogen oxides as carcinogenic, and it is linked to an increased risk of lung cancer.
• Vulnerable groups: Children, the elderly and people with existing respiratory or heart problems are particularly vulnerable.

In another article we will publish, we will show that the illegal amount of NOx emissions from diesel engines in the period 2009-2024 has caused a whopping 124,000 deaths and 98,000 new cases of childhood asthma - and this is only in Europe!

Environmental impacts

In addition to å be dangerous to health, NOx is also very harmful to the environment:

• Ground ozone: NOx, together with short-lived organic compounds under sunlight, contributes to the formation of ground-level ozone, which damages vegetation and human health.
• Particle formation and acid deposits: NOx is part of chemical processes that form secondary particles (PM2.5) and contribute to acid precipitation that damages ecosystems and buildings.
• Local air quality: Road traffic is an important source of NOx in urban areas, and local concentrations can exceed health-related limit values.

NOx is measured both as emissions from sources (tonnes/years) and as concentration in air (µg/m3 over time). The user's monitoring for assess possible regulatory compliance and the impact on public health.

For reflection

In addition to NOx emissions, diesel engines also produce more nanoparticles than gasoline engines. We will not goå in detail about this now, but just briefly remind ourselves of that alsoå they are very harmful, especially for the young and the elderly. 

When sore; diesel engines produce both more harmful gas and more harmful nanoparticles than comparable petrol engines, and this has been known for decades, how could the authorities, with all their resources, have allowed themselves to be hurt; thoroughly wonder what the car manufacturertene claimed that the emissions from their diesel cars were? How could they continue with å make increasingly unrealistic demands on the producers when it should, should, be clear both in view of physics and economics that they were completely unattainable? Alsoå they adjusted the entire tax and duty system for å getting us to å switch to diesel cars, and nå have the same authorities for almost ten years denied that we have suffered damage from this, financially and environmentally, and refused us compensation?

Norway is actually in a special position here, as it is possibly the only country - at least in Europe - where the consumer authorities actively oppose the only measure for getting a bay with the problem!

Conclusion

In the next article in the series, we will look at The EGR function, which can be used for å reduce the combustion temperature and thus, as we have seen, reduce NOx emissions. There are also other systems and measures, such as NOx traps and post-treatment methods that convert NOx into harmless nitrogen and water. The latter is usually known as AdBlue, maybe we can get back to how it works too.

Meanwhile, nå as we have seen in what kind of bullshit NOx really is, and at the same time thinking back on how we ended up here, så is it just one thing å conclude with: If you are not already a member, JOIN PÅ IN THE COMPLAINT CASE THAT IS RELEVANT TO YOU!  It's free å join, and you sign up for here: www.bilklager.no

Together we are strong!

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