Minister for Transport Shane Ross has cited motorists' "inertia" as a reason up to half of electric car owners have not signed up for toll road discounts.
He made the comments as drivers who joined the scheme experience major difficulties getting toll rebates from the initiative Mr Ross launched in July 2018.
The scheme, administered by State agency Transport Infrastructure Ireland (TII), aims to encourage the purchase of emissions-saving battery powered vehicles and applies to four toll service providers.
Electric vehicles qualify for 50 per cent off toll prices and 75 per cent off the M50 toll at off-peak hours, while hybrid vehicles get a 25 per cent reduction. The discounts are worth €500 for private cars and €1,000 for commercial vehicles, annually.
Recent figures show a surge in the number of electric vehicle sales with 811 purchased in January this year compared with 104 for the same month in 2018. Plug-in hybrid car sales rose from 109 in January last year to 301 this year.
Mr Ross said more than 4,000 people, some 52 per cent of electric or hybrid car owners, had successfully signed up for the scheme.
Shock
But Fine Gael TD Noel Rock expressed shock that "only one in every two of them has registered for a scheme that is meant to incentivise the public at large to convert to electric vehicles, turn doubters into believers and get more people buying electric vehicles".
The fact that only half of existing owners had applied for the scheme showed a clear issue with the “clarity, consistency, effectiveness and usefulness of the scheme”, he said.
But Mr Ross said “if 48 per cent of people who qualify are not applying, it could be inertia”. He said it could also be a matter of the scheme not being properly advertised, and he would bring the matter to TII’s attention.
Mr Rock raised the issue following a report in The Irish Times that owners who had signed up for the scheme, which requires a toll tag, had been charged full price.
He said some operators applied the discount the moment a car passes through the toll, while others rebate the money on a monthly basis in arrears, but there was a “complete lack of clarity and consistency” on the issue.
The Dublin North-West TD drives an electric car himself and successfully receives the toll discount.
A spokesman for TII, which has responsibility for the M50 and Port Tunnel, said: “We will implement the Department of Transport directive [on the toll discount] and try to make it as seamless as possible.”
Mr Ross said neither the TII nor individual toll service providers had received “information, concerns or complaints” from customers about the scheme.
However, while toll providers get information about cars from the national vehicle registration office, it has been suggested vehicle registration documentation should carry an extra category indicating whether a specific vehicle is petrol, diesel, electric or hybrid. This could help make it easier for toll providers to identify qualifying cars for discount.