Here's a more detailed procedure that worked for me.
If, after you connect and switch on your scanner, you get the following output from this command,
sudo scanimage -L
No scanners were identified. If you were expecting something different,
check that the scanner is plugged in, turned on and detected by the
sane-find-scanner tool (if appropriate). Please read the documentation
which came with this software (README, FAQ, manpages).
but this command finds your scanner,
# sane-find-scanner will now attempt to detect your scanner. If the
found USB scanner (vendor=0x04b8 [EPSON], product=0x0133 [EPSON Scanner] ...
# Your USB scanner was (probably) detected. It may or may not be supported by
then you need to install Espon drivers.
Visit this page
and enter GT-1500 for the product name, and Linux for the Operating Sytstem.
Eventually, you will need to
download these packages from two separate download pages
Next, install the standard Ubuntu package xsltproc followed by the three pages you have just downloaded
sudo apt-get install xsltproc
sudo dpkg -i iscan*
Afterwards, when scanimage should give you the following output
device `epkowa:interpreter:002:004' is a Epson GT-1500 flatbed scanner
At this point, I could scan using simple-scan.