Tunnelvignette|Construction du tunnel sous la Tamise en 1830. Un tunnel est une galerie souterraine livrant passage à une voie de communication (chemin de fer, canal, route, chemin pour piétons). Sont apparentés aux tunnels par leur mode de construction les grands ouvrages hydrauliques souterrains, tels que les aqueducs, collecteurs et émissaires destinés soit à l'amenée, soit à l'évacuation des eaux des grands centres et certaines conduites établies en liaison avec les barrages et usines hydro-électriques.
Government incentives for plug-in electric vehiclesGovernment incentives for plug-in electric vehicles have been established around the world to support policy-driven adoption of plug-in electric vehicles. These incentives mainly take the form of purchase rebates, tax exemptions and tax credits, and additional perks that range from access to bus lanes to waivers on fees (charging, parking, tolls, etc.). The amount of the financial incentives may depend on vehicle battery size or all-electric range. Often hybrid electric vehicles are included.
Tunnel warfareTunnel warfare involves war being conducted in tunnels and other underground cavities. It often includes the construction of underground facilities (mining or undermining) in order to attack or defend, and the use of existing natural caves and artificial underground facilities for military purposes. Tunnels can be used to undermine fortifications and slip into enemy territory for a surprise attack, while it can strengthen a defense by creating the possibility of ambush, counterattack and the ability to transfer troops from one portion of the battleground to another unseen and protected.
Plug-in electric vehicleA plug-in electric vehicle (PEV) is any road vehicle that can utilize an external source of electricity (such as a wall socket that connects to the power grid) to store electrical energy within its onboard rechargeable battery packs, to power an electric motor and help propelling the wheels. PEV is a subset of electric vehicles, and includes all-electric/battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs).
