The study

  • Why?

The general assumption is that the sharing economy generates a positive environmental benefit and thus reduces resource consumption and CO2 emissions. But what is the actual impact of one rental transaction on Sharely?

We made this study in April 2020 together with the company ESU-services which specialises in life cycle assessment (LCA) methodology.

  • Approach

The 13 most rented articles on Sharely make up 53.8% of all transactions on the platform. The study analysed these 13 most rented articles for their CO2 intensity.

In addition, a user survey was conducted to determine:

1. What the borrowers would have done without Sharely

2. What mode of transport the borrowers used to collect the article from the lender

In this user survey, we received responses from over 190 Sharelians, which allowed us to make our first estimate of CO2 savings based on information from actual borrowers.

  • Results

This allowed us to calculate that 100 rental transactions of the 13 most rented article types on Sharely effectively prevent 52 purchases (and thus their production).

When weighted, this results in a reduction in CO2 emissions of 88.4 kg per evaluated rental transaction.

Between 2017 and 2019, Sharely saved the equivalent in CO2 emissions of a car journey of
3,830,000 km.

Not detailed enough yet? Ok, get ready for a deep dive.

Part A:

Identify CO2 intensity of the articles

In this section we determined with ESU-services the greenhouse gas emissions in CO2 equivalents for the 13 most rented article types on Sharely.

Two approaches were available for calculating the CO2 intensity of an object production:

1. We calculated the CO2 value per kilogram of an article type and multiplied it by the total weight of the article

2. We calculated the CO2 value per CHF purchase value and multiplied it by the purchase price of the article

The result from the above calculations showed that an article from the Top 13 list has an average impact (production and disposal) of 310.53 kg CO2-eq. This result is weighted, which means that the number of transactions was taken into account.

Part B:

Identify the avoided "new purchases"

We determined what proportion of Sharelians would have bought an article if Sharely did not exist. To do this, we conducted a survey among our users to find out what proportion of people would have foregone an article because of Sharely.

For every 100 transactions on Sharely, 52 new purchases are avoided.

Not all rented articles types are equally CO2-intensive, so we cannot assumat that the CO2-eq impact per rental transaction will also decrease by 52%.

Taking into account the CO2 impact for each article type, we obtain a 30% reduction in CO2-eq (i.e. a CO2-eq reduction factor od 0.30 for each transaction).

With a calculated saving of 52 or 30 CO2-weighted article per 100 transactions, Sharely leads to a significant reduction of CO2 and resource consumption.

Part C:

Calculate the gross CO2 savings

Using the figures from parts A and B, we were able to calculate the gross savings in CO2.
Per transaction, a gross saving of 94.7 kg CO2 is achieved.

From this value, the rebound effects still have to be determined and taken into account.

Part D:

Estimate the impact of the transport

We determined with which type of transport the borrowers used to collect and return the articles from the lenders.

When the borrower doesn't travel on foot, there is a rebound effect due to the collect and transportation of the article. The chosen type of transport is decisive here, as the CO2 impact varies greatly. The CO2 emissions of this "logistics" had to be subtracted from the gross value saved from part C.

The result of the survey showed that each transaction causes an average of 5.6 kg CO2-eq for transportation. This is mainly caused by objects that:

a) are thematically linked to the car

b) have a high dead weight and are therefore transported by car

The "article logistics" thus causes a rebound effect of approx. 6% (5.6 kg CO2 vs. 94.7 kg CO2 gross CO2 savings).

Part E:

Assess the additional damages

A second rebound effect arises from the additional damages caused by renting - and thus, using more - an article on Sharely. An article that breaks due to a rental on Sharely has to be repaired or replaced, which reduces the carbon footprint of the rental.

To get meaningful data, we evaluated how many damages were reported to us for each of the 13 article types from 2017 to 2019. This allowed us to calculate the total loss rate per article type.

Our evaluation showed that, for every 100 transaction, 0.47 articles suffered a total loss on average. The necessary replacement purchases generates CO2, which has to be considered as a rebound value. The total value for the years 2017 to 2019 amounts to 3.8 tons of CO2-eq.

These "replacement purchases" therefore create a rebound effect of about 0.7% (0.64 kg CO2 vs. 94.7 kg CO2 gross CO2 savings).

Part F:

Net CO2 savings per transaction

This gave us the net CO2 savings achieved per rental transaction on Sharely.

The net CO2 savings over all transactions and per transaction was calculated. The result is the gross saving minus the two rebound effects.