A scale showing both an electric battery and a hydrogen battery

In four scenarios — low and high use, on clean and dirty grids — the Tesla battery electric consistently outperforms a Nikola fuel cell truck, according to analysis by Vision Mobility

New research comparing the lifetime CO2 emissions of a Tesla Semi, a fully battery electric truck, and Nikola One/Two fuel cell electric trucks, provides valuable insights regarding just how low the emissions of these two low-emission vehicles are over a decade.

According to James Carter, principal consultant at Vision Mobility, which conducted the study, sizing up the two big-name, low-emission freight trucks was warranted by “the crazy rises in the stock prices of both Tesla and Nikola recently, as well as the ongoing debate about which energy system will be better for long-distance trucking and heavy-duty applications.”

The study projected the lifetime emissions for both vehicles across four possible use scenarios, with other factors such load weight, refueling times and vehicle cost not taken into account.

Spoiler alert: in all cases, the battery electric is the better performer, a gap that widens as distance driven and grid CO2 increases.

Usage and embodied emissions

The first scenario projected the results of an average level of use (100,000 kilometres driven per year) and a very low-CO2 electrical grid (40 g/kWh), as is found in Ontario, over a 10-year period. The Tesla truck requires 125 kWh of electricity to travel 100 km. Based on Nikola’s stated power rate of 7.5 miles per kg of hydrogen, the electricity required to produce enough H2 to power the Nikola truck for the same distance is 509.8 kWh.

ScenarioPercentage higher CO2
1 Average usage, clean grid69
2 High usage, clean grid134
3 Average usage, dirty grid253
4 Low usage, clean grid29

Source: Vision Mobility

Vision Mobility’s study also took into account the embodied emissions produced through the manufacturing of each vehicle’s battery. For the Tesla’s 1,000 kWh battery, that means factoring in 83,000 kg of additional CO2, and 20,780 kg for Nikola’s 250 kWh battery.

After adding the usage emissions over the course of 10 years to the embodied emissions, Vision Mobility’s calculations found the Tesla would produce 133,000 kg of CO2 over the decade while the Nikola would generate 224,698 kg. That represents a 69 per cent higher level of emissions for the fuel cell vehicle.

Higher kilometres, similar results

The second scenario assumed a high amount of kilometres driven (200,000 km per year) on the same low-emission grid. In this case, the Tesla Semi was projected to produce only 183,000 kg of CO2 over 10 years, whereas the Nikola One/Two would produce 428,617 kg, which means 134 per cent higher lifetime emissions.

The findings of the third scenario, which projected the results of an average amount driven (100,000 km per year) on a grid dependent on an average level of CO2 (400 g/kWh), were even more striking. The Nikola was calculated to produce 2,059,964 kg of C02 over 10 years, a number 253 per cent higher than the Tesla’s 583,000 kg.

The fourth scenario projected the results of very few kilometres driven (50,000 per year) on a very low-CO2 grid (40 g/kWh). Nikola’s lifecycle emissions still topped Tesla’s, albeit this time by a much slimmer 29 per cent.

Looking forward

Given these calculations, Tesla’s BEV scores a clear victory over Nikola’s fuel cell vehicle in terms of lifetime CO2 saved.

The vehicle’s real-life emissions totals could vary to a significant degree depending on factors such as differing climates, freight loads and available refuelling infrastructure — a point argued by Nikola founder and executive chairman Trevor Milton in this recent post. However, Vision Mobility’s findings demonstrate that across a number of scenarios, battery electric still seems to be the superior pick from an ecological standpoint.

The CO2 projections for the hydrogen vehicle are also based on the assumption that only green H2 would be used for fuel. Given that 96 per cent of H2 is currently drawn from steam reforming of natural gas, such sourcing is rarely available.

Carter, in summarizing his company’s research, also points out that the near future may see Tesla take its lead even further as embodied emissions in battery manufacturing continue to drop due to technological innovation. As he puts it, “the outlook on changes to these assumptions moving forward favours the Tesla.”