The use of solar energy and wireless eliminates any need for re-wiring the hotel room meaning that installation is significantly simplified in existing hotel buildings.

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"At three of these locations our investigations concluded that the noise should be mitigated through the installation of low noise surfacing materials when the existing surface is worn out, in accordance with our maintenance policy, " said an agency spokesperson.

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According to Department of Energy researchers, factoring in capital costs, one kwh of power generated by a new solar installation costs on the order of 25 cents, even with existing incentives.

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