Two days ago, I shared my recent comments from Foodlog on this blog, where I highlighted the large-scale figures of energy consumption in the Netherlands. Hendrik Kaput often emphasizes the staggering size of these numbers, and he’s right. These figures are so immense that the sheer number of zeros can make them hard to grasp. To complicate matters, we use different units interchangeably, which only adds to the confusion.

The Challenge of Mixed Units in Energy Discussions

Energy is traditionally expressed in Joules (J) and its multiples (kJ, MJ, PJ, etc.). In practice, however, we also use kWh (and MWh or billion kWh). The conversion factor between Wh (=J/s per hour) and J is 3600 seconds. Energy consumption or generation over time is expressed in Watts (Joules per second), but since one Watt represents very little power, we typically talk about kW, MW, or GW. Below, I outline the figures and their conversion factors.

At the climate tables, the discussion often shifts to tons of CO2 equivalents. This choice is either:

1. A deliberate political decision influenced by lobbyists, or
2. A significant oversight by policymakers.
   From a scientific or technical perspective, this is highly inefficient. This is why I strongly oppose the use of CO2 equivalents in discussions and calculations. Instead, we should focus on standard units of energy and power as defined in the SI system: PJ, TWh (for energy), and MW (for power). Here’s why:

Why the Use of CO2 Equivalents is Problematic

1. Ambiguity in Climate Impact
   The relationship between CO2-equivalent emissions and global warming is subject to ongoing debate. The precise link between atmospheric CO2 concentration and weather or climate remains uncertain. To avoid entangling myself in these contentious discussions, I have decided to steer clear of them altogether.
2. Different Sources, Different Effects
   CO2 released from the digestion or combustion of plants is chemically identical to CO2 emitted from burning natural gas or oil, but their net effects on the atmosphere differ. Biological systems (plants, digestion, animals) operate largely within the short CO2 cycle and have minimal net impact on atmospheric CO2 concentration (and thus global warming). The focus should be on reducing the use of fossil fuels like natural gas, oil (and derivatives), and coal—the primary drivers of increased CO2 concentrations.
3. Confusion in Balances
   Many articles conflate net increases in emissions with figures related to the balance (emissions minus uptake). For example, until about 100 years ago, humanity primarily burned wood, which could be considered an anthropogenic emission. However, this had no lasting effect on atmospheric concentrations because it was part of the short carbon cycle. What matters now are additional emissions from the long carbon cycle, derived from mining products like coal, oil, and gas.

A Look at the Dutch Energy Balance

The difference between energy balance (inputs, outputs, and consumption) and actual energy use can best be illustrated by looking at the total energy balance of the Netherlands in 2015 (unfortunately, I do not have more recent data). In 2015, we imported approximately 11,000 PJ of energy (primarily crude oil and natural gas). Here, “imports” also include the extraction of natural gas in Groningen. We exported about 8,500 PJ and consumed roughly 2,500 PJ domestically. A visual representation looks like this:

On the right side of the diagram, you see the actual energy consumption in the Netherlands. This is divided into industry, transport, residential heating, and non-energy uses. Looking solely at consumption, the breakdown in detail appears as follows:

On the left, you see the energy sources, and on the far right, how these sources are utilized. Purple represents crude oil, dark blue is natural gas, and light blue is electricity. Together (in 2015): 2,400 PJ, or 657 TWh (= 657 x 10^15 Wh or 657 billion kWh).

Addressing Technical Oversights in Energy Calculations

Actual consumption is likely 300–800 PJ higher. Why? Because generating electricity often involves burning natural gas or coal, which produces significant residual heat that is effectively wasted. This is why I advocate for utilizing residual heat wherever possible, such as for residential heating, hot water, or industrial processes. Have we heard this discussed at the climate tables?

Additionally, the conversion of crude oil into gasoline and other derivatives should be considered. Some energy experts therefore prefer discussing 2,800–3,200 PJ of actual energy consumption. While I’m open to either figure, it’s crucial to focus on the broader picture.

Conclusion: Simplifying the Debate

The current debate on energy and emissions is unnecessarily complicated by confusion over units and figures. By focusing on clear, universally accepted measurements like PJ and TWh, and by addressing the potential of residual heat, we can make significant progress toward a more sustainable energy system. Let’s simplify the conversation and prioritize solutions that matter.