Energy Efficiency Improvement Act of 2014

Energy Efficiency Improvement Act of 2015 - Better Buildings Act of 2014 - Requires the General Services Administration (GSA) to: (1) develop and publish model leasing provisions to encourage building owners and tenants to use greater cost-effective energy efficiency and water efficiency measures in commercial buildings, and (2) develop policies and best practices to implement the measures for the realty services provided by the GSA to federal agencies.

Amends the Energy Independence and Security Act of 2007 to require the Environmental Protection Agency (EPA) to develop a voluntary Tenant Star program within the Energy Star program to recognize tenants of spaces in commercial buildings that voluntarily achieve high levels of energy efficiency. Authorizes the EPA to develop a voluntary program to recognize commercial building owners and tenants that use high-performance energy efficiency measures in the design and construction of leased spaces.

Amends the Energy Policy and Conservation Act to prescribe additional energy conservation standards for grid-enabled water heaters for use as part of an electric thermal storage or demand response program, which is a program that enables customers to reduce or shift their power use during peak demand periods.

Energy Efficient Government Technology Act - Amends the Energy Independence and Security Act of 2007 to require: (1) each federal agency to coordinate with the Office of Management and Budget (OMB), the Department of Energy (DOE), and the EPA to develop an implementation strategy for the maintenance, purchase, and use of energy-efficient and energy-saving information technologies; (2) DOE to maintain a data center energy practitioner program that leads to the certification of energy practitioners qualified to evaluate the energy usage and efficiency opportunities in federal data centers; and (3) DOE to establish an open data initiative to make information about federal data center energy usage available and accessible in a manner that encourages data center innovation, optimization, and consolidation.

Requires DOE to maintain, and if necessary create, a database for storing and making available public energy-related information on commercial and multifamily buildings.