CERES Fair Food delivers organic groceries to households across Melbourne, sourced from over 150 farmers and ethical grocery makers. They support regenerative farming practices and closed loop waste cycles, provide employment and career pathways for new migrants, and return 100% of profits to CERES environmental education programs.
With their warehouse already powered entirely by rooftop solar, the launch of their introductory EV Fleet is incredibly exciting and brings the social enterprise even closer to offering emission free grocery delivery. It’s a step CERES Fair Food hopes will inspire further action by demonstrating real-life options for households and businesses alike.
Loan amount: $82,000 (TBC)
Loan repayments: TBC
Status: Current project
Delivery date: TBC
2 Ford e-transit fully electric refrigerated delivery vans
2 Smart solar chargers
1 charger hub
Cost: The CORENA loan will contribute $70,000 towards the total vehicle cost ($170,000) and approximately $12,000 to cover the cost of charging equipment and installation.
Expected savings: TBC (approx 5 year payback)
Reduction in carbon emissions/yr: We anticipate that excess solar generated on site will provide at least half of the electricity used to charge the vehicles. We will provide more details when figures from actual operation are available.
Case Study so far…
Vehicle choice: Two Ford e-transit delivery vans
This part was easy because no other fully electric delivery vans of a suitable size for Fair Food deliveries are available in Australia yet. Fair Food have ordered two Ford e-transit vans, and they’ll arrive here in mid-2022. Refrigeration equipment will then be added to both vans, bringing the total cost to $170,000. Fair Food have received a partial grant, and the CORENA loan will make up the shortfall of $70,000 and also cover the purchase and installation costs of charging infrastructure.
Ford e-transit vans have 68kWh battery pack and a range of ‘up to 317km’, but real world range figures will inevitably be lower depending on cargo load and driving conditions. For our conservative calculations so far we are assuming a range of 227km, but that is more than enough for even the longest of Fair Food’s nine delivery runs, made with a fleet of eight vehicles.
The EVs will be replacing two Toyota LWB Hiace refrigerated vans. Each of those have annual running costs of $8,779, and carbon emissions of around 16 tonnes/year per vehicle.
Charging infrastructure choices
Initially we considered three different options:
- A 25kW DC rapid charger capable of fully charging one van in 2.7 hours and costing over $20,000
- Two 7-11kW AC wall chargers capable of fully charging a van in 6.2 hours and costing around $8,000 for the two
- Two 15A 3.6 kW AC granny chargers capable of charging enough overnight between runs, and costing around $3,000 for the two
Any of those options would be workable, but Fair Food want to maximise use of their massive amount of excess solar generation (46,670kWh in 2021). Even though they currently export more than enough excess solar generation to keep both vans fully charged (17,000kWh/year for two vans), any of those options would inevitably result in the use of large amounts of daytime grid electricity for charging the vans.
The 25kW DC and 11kW AC chargers take electricity faster than the excess solar is being generated during many months of the year, meaning daytime charging would be via a mix of grid and solar electricity. This is particularly so since there are regular large peaks and troughs in the amount of excess solar being exported due to cool room operation at the warehouse. In addition, the delivery schedule means that vans are only at the warehouse either before mid-morning, after mid-afternoon, or for an hour in the middle of the day.
A granny charger could be used for daytime charging without using much daytime grid electricity at all, but they are too slow to do much charging during the few daylight hours vans are typically at the warehouse, so the majority of charging would have to be done overnight using off-peak grid electricity.
But then we stumbled across Zappi solar smart chargers! These are perfect for avoiding the drawbacks of the above chargers, and come highly recommended by a couple of happy users.
The three-phase AC Zappi operates at up to 22kW, but a Ford e-transit will only accept up to 11kW AC charging. That means it is not super fast, but when used in ECO+ mode it uses only excess solar. If there is no excess solar it stops recharging, then restarts again when excess solar is available. By plugging in the EV vans as soon as they return to the warehouse, they can make use of however much or little excess solar is currently available without risking using any peak-rate grid electricity. The Zappi can then be programmed to finish charging overnight, if necessary, in FAST mode during off-peak hours.
Even during mid-winter Fair Food is exporting at least some excess solar generation. By using Zappi chargers they will be able to make full use of excess solar all year round without using any grid electricity at daytime peak-rates.
Savings on running costs
Having settled on using two Zappi smart chargers, we then examined the solar monitoring records to determine the amount of excess solar exported each month in 2021 during the time slots that vans are at the warehouse. We then calculated the average excess solar per day that would be usable by the EVs.
For example, if EV1 is used for the first and last runs of the day, it will be at the warehouse for around one hour in the middle of the day. We calculated that on average 10.5kWh of excess solar could be used by EV1 during that one hour of peak solar generation. During summer months the available amount would often be more than the 11kWh that a Zappi can take during one hour, so we adjusted for that, then calculated the kWh of excess solar that would be used over the course of a year to recharge EV1 (4,365kWh.year).
We multiplied the km/year for those two delivery runs by our assumed ‘real world’ kWh/km figure to obtain the total kWh/year needed by EV1, then subtracted the above kWh of excess solar use to obtain the kWh of off-peak electricity that would need to be used overnight to keep EV1 sufficiently charged: 42% excess solar and 58% off-peak overnight electricity.
Next we calculated the annual electricity cost assuming 42% at feed-in tariff rates and 58% at off-peak grid electricity rates, which comes to $1,344/year. Average annual diesel fuel costs for Fair Food delivery vans is $7,328.
If EV2 is used for the second delivery run each day, it would return to the warehouse around 3:30pm and would continue to be charged using solar-only mode for the rest of daylight hours. In mid-winter there would not be a lot of excess solar during that time, but during many months of the year, and particularly during daylight savings months, there is still plenty of excess solar being exported that late in the day. We calculated EV2 would use 65% excess solar and only 35% off-peak overnight electricity, resulting in an electricity cost of $654/year.
Accordingly, the $50,000 extra cost involved in purchasing these two electric delivery vans rather than diesel alternatives, plus around $12,000 for the two Zappi chargers and their installation costs, will be repaid via reduced running costs in 4.7 years.
Overall 53% of the electricity used for charging the two EVs will be excess solar generation. If the other 47% (7,888kWh/year) were regular grid electricity (it won’t be in this case), it would produce 5.36 tonnes/year of carbon emissions (using NEM average 0.68kg/kWh carbon intensity figure for 2021). That is a lot less than the 32 tonnes/year of carbon emissions resulting from running the 2 diesel vehicles that are being replaced.
If the two new EVs were to be kept charged entirely using grid electricity, that would produce 11.4 tonnes/year of carbon emissions. The carbon intensity of grid electricity has been falling steadily and will continue to do so over coming years, so switching to EV delivery vans will become increasingly effective at reducing carbon emissions even if charged entirely with grid electricity.