Interview with Sales & Marketing Director, David Thackray


The Food Service industry, servicing inner cities and urban areas is widely implicated in the move to Zero Emission Zones and is a fast moving and innovative sector, characterised in recent weeks by its dramatic business model changes to address the current COVID crisis. Supplying key workers, creating home delivery services, cooking and delivering meals to care homes and hospitals, and more.  Thomas Franks Feeding Communities Project is a prime example, also Savona Foods Home Deliveries to alleviate the need for key workers to go to supermarkets or wait for available delivery slots from supermarkets.

This adaptability explains why foodservice companies have been some of the first to want to adopt REEV technologies to enable zero emission deliveries in urban areas. Recent Tevva press coverage has showcased several foodservice companies, whether a direct purchase, or as early participants in the Tevva electrify initiative announced lated 2019.

The food-service industy faces particular challenges with regards to fleet electrification, and since we arent able to visit customers or travel ourselves at the moment, we were able to pin David down to a useful interview to address some of the FAQ’s regarding how our technology works particularly well for this sector!

1. What are the key challenges with electrifying urban distribution?

In short, range and payload – which combine to determine the economics of ownership and operation.
First, range. EVs do not have a short range, they have an inconsistent range. This is particularly dependent on a) external temperature and b) driver behaviour.
It’s a fairly widely recognised fact that battery powered vehicles have reduced range in notably cold conditions. What is perhaps not quite so widely understood is that this variation can push towards two to one ratio – that is to say that range in the coldest conditions can be roughly half what is was in the most ideal climate.
There are two reasons why driver behaviour is more impactful in an EV than in a traditional diesel vehicle. Most obviously, the diesel doesn’t have re-gen braking whereas the EV does. The extent to which the driver maximises that opportunity bears significantly on the range achieved. The other reason is connected to the acceleration capability of the EV. EVs have a well-deserved reputation for being quick off the line; that enables a heavy footed driver to use more power more quickly than he or she could in a diesel vehicle. In an urban, stop-start cycle, these two things can make a very large difference to the ‘fuel consumption’ of the EV. The author, along with other members of the Tevva staff, has returned energy consumption figures (over very extended distances and time) that are fully one half of the average seen in some customer vehicles of broadly equivalent type.
From the above it can be seen that there is great scope for range variation. Such variation can be easily provided for by fitting a very large battery and indeed, in the passenger car world, this is often done – witness the 100kWh battery on some Tesla models. However, this solution is not suited to a goods vehicle for two reasons:
1. Batteries are relatively heavy and so impact payload
2. Batteries are relatively expensive (if becoming progressively less so)
It does not matter that a Tesla Model S weighs  2300kg and as a luxury product, the price tag is equally not a barrier. Conversely, a goods vehicle exists to carry freight at minimum cost, and it does so subject to strict gross vehicle weight limits. Thus, bigger batteries mean a lower payload at a higher cost – never a winning combination.
Overcoming this conundrum is at the heart of making an economically effective electric goods vehicle.

2. Are there any additional challenges with electrifying refrigerated urban distribution vehicles?

Deploying a battery electric vehicle on temperature-controlled duty cycles such as (typically) fresh food delivery adds a further substantial variable to the overall energy requirement of the vehicle.

The energy required to maintain the load area at, for example 4 degrees C will vary based on:
• The ambient outside temperature
• The number of deliveries on the route (number and duration of vehicle openings)
• The ratio of filled space to empty space in the compartment
Clearly, at 30 degrees C in Summer, a chiller unit will work much harder than on a winter day at 6 or 7 degrees – even if the compartment is left unopened. If operating on a multi-drop cycle, the diligence of the driver in using curtains will be impactful and if the compartment has a greater unfilled volume, the evaporator unit will again need to work harder.

Once again therefore, we can project wide variation from the most benign to the most challenging duty cycle. However with a chiller unit drawing a typical maximum of 4-6kWh per hour whilst loaded, which is typically half to two thirds of the shift but can be for the full shift; it might be reasonable to estimate that the additional energy requirements for temperature-controlled vehicles might equate to between 20% and 70% of an 80kWh battery pack – greatly increasing the challenge of reconciling vehicle range and payload.

3. What exactly is the REX, and why is hitting the spot for dairies, chilled foodservice and others?

A range extender (REX) is an alternative technical solution to the deployment of greatly increased battery capacity. The reason this difference matters is simple: money.
Even with all the variabilities already described, it is easy enough to build a truck with still enough battery capacity to meet all the worst-case scenarios together. Such vehicles have seen exhibited in concept form at trade shows over the past 2-3 years with battery installations of 250-300kWh.
Unfortunately, that’s around 3 tonnes of battery and somewhere in the order of £60,000 of battery. This translates into (for example) a 12t GVW vehicle costing more than twice as much as its diesel counterpart whilst having approximately half the payload. Such a vehicle will never make economic sense, will never be deployed and will therefore never achieve any environmental advantage.
Conversely, a battery electric vehicle with an on-board generator (range extender) can achieve an effective ‘happy medium’. Combining a modest (80kWh) battery giving a typical 120km zero emission range with a low weight low cost on-board generator means a 12T GVW vehicle can retain around 85% of the payload capability of the diesel it replaces with a capex uplift that’s low enough to be fully offset by greatly lower operating costs. Sure enough, on the worst case scenario days, the vehicle will produce some emissions, but it will eliminate between 90% and 95% of its total lifetime emissions and it won’t ever run flat and need a recovery truck – not oven if it is sent on a 500 mile route.
This absolute flexibility gives foodservice operators both the operational confidence and the financial justification to deploy electric vehicles in volume.

4. Why is REX a more environmentally friendly and sustainable solution than pure EV?

Sir Winston Churchill once said of a document he received: “The length of this document defends it well against the risk of its being read”.
The same might be said of a super-heavy, super-expensive mega battery 12T truckThe size of this vehicle’s battery defends it well against the risk of its being purchased. So, what about an EV with a ‘right size’ battery but no ranger extender? Such a vehicle will indeed have a better price point and payload, but it will have limitations on its deployability. Without a range extender its battery condition is binary -either it has charge and it drives, or it runs flat and it stops. Given those risks and the variations we have already described, it will be deployed on routes that equate to 90% of the expected worst-case scenario – otherwise described as ‘not very far’.
The nuance here is that to be truly environmentally friendly we must electrify miles rather than vehicles. A truck that eliminates 95% of the emissions from 200,000 miles over 5 years is better for the environment than another that eliminates 100% of the emissions from 100,000 miles over the same period. That’s what REX technology delivers. There is an aggregate requirement for a certain number of freight miles to be completed if we are to have food on the shelves, and if your EV does half the duty of your other vehicles, the other half still needs doing – either by a second EV (not economic) or by a diesel (not good for the environment). Simply put; REX equals more electric miles equals more environmentally friendly.

5. How do you ensure the integrity of the REX in a designated Clean Air Zone, ULEZ or other?

This is done by the use of Geo-Zones and, in Tevva’s case, by the use of patented Connected Autonomous Vehicle (CAV) technology.
Any Clean Zone (CAZ), Zero Emission Zone (ZEZ) – or similar is defined by a set of GPS points to form a continuous boundary to the zone (a Geo Zone). Within such a zone, the range extender is prevented from operating except in an emergency. Such an emergency is virtually inconceivable because of the predictive energy software that underpins the system.
The Tevva REX is entirely autonomous (the driver has no controls to switch it on or off). Tevva REX is governed by cloud-based software called Predictive Range Extender Management System (PREMS). PREMS calculates expected energy use based on GPS route data and deploys the REX proactively and ahead of time, if needed, to ensure that all of the time spent within any CAZ/ZEZ can be driven in full zero tailpipe emission mode.
What this means in practice is that the vehicle can make massive contributions to the Climate Emergency by eliminating 95% of its lifetime CO2 emissions whilst fulfilling the same duty cycle as a traditional diesel and at the same time, it satisfies the neds to the Public Health Emergency by guaranteeing zero tailpipe operation in urban areas.
Furthermore, all of the above can be verified via the extensive telematics suite built into the Tevva system – opening the potential for city authorities to manage CAZs without the need for hugely expensive cordons of ANPR cameras.

 In Summary

All commercial freight vehicle duty cycles give rise to substantial variations in the energy requirements from the battery, but temperature-controlled operations redouble those uncertainties. To meet all the potential needs, a battery electric vehicle (BEV) without a range extender will need a battery of a size and weight that renders the vehicle economically unviable.
Range-extender technology, coupled with autonomous predictive software enable the deployment of fully electric vehicles, irrespective of duty cycle and critically, at a competitive total cost of ownership.

Find out more about Tevva electrify campaign, or contact one of our fleet electrification experts today.