The internet is a cornucopia of detailed information. Whether someone is looking for information on their favorite book, or browsing to reminisce by watching their favorite coconut toting knights, it can be found on the internet. Unfortunately, this availability also leads to vast amounts of, ugh, less than accurate information. Specifically related to energy efficiency, there are several great places to find detailed technical information.
There are two great places to find equipment information and specifications. The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) has a vast database of capacity and efficiency data for a wide range of typical residential and commercial HVAC and water heating products. The Compressed Air and Gas Institute (CAGI) is the de facto gold standard for compressor information and efficiency ratings. Equipment manufacturer websites can be useful for finding basic information, but often can be difficult to navigate.
Appliance standards are most easily found from the Appliance Standard Awareness Project (ASAP). The Department of Energy Office of Energy Efficiency and Renewable Energy (EERE) is the repository for all federal energy efficiency standards. Navigating their website can be a bit tricky, but is often easiest if a specific technology or equipment type is the search target. The EERE also keeps tabs on state level energy codes and provides nice overviews of the various codes currently enforced. To really get into the weeds, ASHRAE 62.1, 62.2, 90.1, and 100, along with their complimentary IECC code versions, will provide the building design, controls, and equipment specs buildings need.
Engineering Information and Assumptions
Engineering Toolbox has more equations, constants, and conversion factors than most people will ever need. However, the local version of a Technical Reference Manual (TRM) is a great location to find actual predicted energy savings for a wide range of efficiency measures. These are all often available with minimal search effort, such as the TRMs for MN, IL, AR, VT, CT, ME, the MEMD, the Mid-Atlantic TRM, and the Regional Technical Forum (RTF).
When researching things on the internet, the goal is to get accurate information and data, not an opinion. A lot of blogs, bulletin boards, and case studies contain useful information, but it generally comes with a slant. Catchy phrases and numbers that seem like they are too good to be true often are. And never accept a savings claim as is. The internet makes it very easy to find lots of information, but don’t just look at one source. Scan a few, and come up with an answer that makes the most sense for the situation at hand.
 In case you don’t know, they were carried by African swallows.