Consumer surplus
The definition of consumer surplus is the difference between the total amount that stakeholders are willing and able to pay for a product, good or service and the total amount that they do pay (i.e. the market price). This is the value that consumers place on accessing resources over and above any costs that may be incurred to obtain them.
In simple terms, if you would be willing to pay £1.60 for a cup of tea but can buy it for £0.90 – the consumer surplus for that person is £0.70. For example, a study might show that for every $1 of public money spent, users received more than $4 of direct benefit in consumer surplus terms.
See Case study 3.5: The value of the British Library in Delivering Impact with Digital Resources.
See also: Tessler, A. (2013) Economic Valuation of the British Library. Available at: https://www.oxfordeconomics.com/my-oxford/projects/245662