The group falls under the auspices of the ministry of finance and its report directly contradicts the government position.
If the money were instead to be invested in the global emissions trading system it would result in forty times the environmental benefit of the proposed railway from Stockholm to Malmö and Gothenburg, the report says.
The government wants to invest in the high-speed rail links in order to reduce emissions of greenhouse gases and boost economic growth.
The expert group has however drawn entirely different conclusions, according to Jan-Eric Nilsson and Roger Pyddoke who presented the report to the government on Friday.
If the Götaland railway were to be constructed, Sweden would sustain a fiscal deficit of 16 billion kronor ($2.2 billion) and would cut annual emissions from the transport sector by 150,000 tonnes – less than one percent, they write in a debate article published in the Dagens Nyheter newspaper.
If the money were instead placed in the international system of emissions rights trading then global emissions would decline by 40 times as much – 5.4 million tonnes per annum.
The National Rail Administration (Banverket) analysis also shows, according to Nilsson and Pydokke, that the project is unprofitable.
The benefit to society of the project does not even amount to its financial cost and comes in at only 89 percent, the pair argue.