June 20, 2017

Prime Now or Prime Later?

Recently Amazon Prime Now has come up in a number of conversations I have been involved with. One group complained that they were running out of beer, and rather than going to get some they joked about ordering some on Prime Now. For those who have not yet heard of Amazon’s Prime Now, it is a home delivery service that offers one or two hour shipping on over ten thousand items. It is available to Amazon Prime members in select areas for free when using the two hour delivery, but it is $7.99 if you want one hour delivery. They serve 30 different major cities, originally in Manhattan and now across the US and even in London. Prime Now requires that you order a certain dollar amount from each store you purchase from and often requires that you are present at delivery. Having learned a little bit about Amazon Fresh and other food delivery companies, I began to wonder whether or not this service would reduce emissions like other delivery services can, if routed efficiently. Or, whether it was just another way for Amazon to gain a larger market share over retail stores. I assumed that this service would not have a high enough demand in a given time window in order to justify a longer trip with more stops. Typically, in order for home delivery  to reduce gas consumption, it requires that the person lives outside of a certain threshold from a grocery store. I live about 0.6 miles from one, which is much less than these typical thresholds. With this in mind, and the thought that they would have a larger less fuel efficient truck like most delivery services, I figured it was very unlikely that they would be able to reduce emissions with this method. However, I wanted to see for myself, so I decided to make an order on my own and ask the driver some questions once he got to my house.

First I had to download the Prime Now app and enter in my area code to confirm that I was in an area that Prime Now services. Then I picked out a couple of products and tried to check out but realized I had a minimum on the number of items I could get. So I adjusted my shopping cart. I ended up buying a couple packs of berries, some deodorant, and some Snickers. I went for the two hour time window because I didn’t want to pay extra. I selected a 6-8 window and it notified me that I had to be there on arrival because I had perishable items. After a $10 discount code, my order came to just over $10 plus a recommended $5 tip for the driver. Once I completed the order, it showed me where my items would be packaged, which was 137^th and Aurora ave, approximately 6 miles from my house. The driver arrived at 7:30 in a Hybrid Toyota Camry, not a bigger truck like I suspected, after making 8 previous stops along the way and I was the final and furthest stop.

Overall I was satisfied with the experience besides having to be at home for the time window. However, my main interest was whether or not Prime Now had reduced emissions. I live 0.6 miles from my preferred grocery store, and assuming I would have driven a Subaru Forester (the most sold car in Washington in 2014) getting 24 mpg city, I would have used 0.05 gallons roundtrip just to get to the grocery store. Assuming all 9 people on my route had the same vehicle and same distance to the store (summed up 10.8 miles), this would be 0.45 gallons of gas for all 9 trips. For the Amazon Now driver, his Camry Hybrid gets 42 mpg in the city but he traveled at least 12 miles roundtrip if the driver took the quickest route from Amazon to my house. (In reality he certainly had to detour to make his stops, but we don’t know how much, so this will suffice.) This would be a total of .29 gallons of gas used for this single trip, which is less than what would be used by each of the nine customers driving separately. However, the total miles traveled is 1.2 miles more with this delivery method, so the difference in vehicle type is really what is making the Amazon Now more efficient. Had my driver been driving a Forester, then he would have used 0.5 gallons rather than the 0.29 in his Camry Hybrid.

In this overly simplified scenario, Amazon Now would be reducing the total gas consumed, however the total driving distance was increased. In addition, by changing any one of these assumptions, the outcomes will be completely different. What it comes down to, is that in order for this service to be more efficient in terms of gas use, the drivers must be using efficient vehicles, there must be deliveries near each other or on the way, and there must be a larger amount of them to make up for the relatively far distance from the Amazon location compared with to a local grocery store. From this I am still uncertain whether it is better to order from Amazon Now because its efficiency is dependent on a number of variables, however, if you live in an area far from a grocery store, you drive a gas guzzler, and many people around you already order from Prime Now, then using the service will probably decrease the amount of gas used for these trips. However, it is unlikely that the trip made by Amazon Prime Now will actually replace any trips that you would have taken. In my case I normally walk or take the bus to the store so in reality, using a service like Prime Now will actually increase emissions for someone like me. With this in mind, I suspect that overall this new service is not going to reduce emissions.