Grid connection

This is regulated by the Natural Gas Act, see Technical standards.

Refusal of grid access

As long as the requested gas quality is upheld, there exists no formal way to refuse grid access.

System usage fees (non-discrimination?)

Nothing formal or publically available, but has been discussed brieflly by the Energy Market Inspectorate in its publications

Connection cost burden sharing

All costs are covered by the 3rd party willing to inject into the grid. However, the Energy Market Inspectorate proposed in 2010 to the government that he augmentation to natural gas quality and the grid injection of biomethane should be a natural part of the grid operation, and thus be a responsibility of the grid owners, while the upgrading and cleaning of the biogas still should be the responsibility of the biogas producer or buyer. See “Förändrade marknadsvillkor för biogasproduktion EI R2010:17 (Changed market conditions for biogas production)”. However, no progress has been seen so far.

Network extension

The EMI discusses the alternatives for governing extensions with respect to optimizing the biomethane market expansion in section 5.6 of its publication ”Ökad andel biogas på en utvecklad gasmarknad EI R2009:12 (Increased share of biogas in a developed gas market)”. Government intervention regarding planning and building is deemed to be able to support the extension in the most optimal way for biomethane, while commercial initiatives from the grid owners allegedly would focus on the increased use of natural gas. A third alternative is to continue as is, with the current building of local grids eventually becoming regional grids which may be connected to the main grid. The disadvantage is the slower process and suboptimization regarding societal needs.
Net extension of the current grid is vehemently opposed by the solid biofuel market, which are very strong lobbyists in Sweden. From a political point of view, natural gas is as fossil as oil. The biggest fear is lock-in effects. LNG has been shown to break the stalemate, getting support from the decision makers.
The TSO Swedegas is actively investigating the possibility of investing in local grids, interconnections and connection to the main grid.