Counting carbon is getting easier. Counting carbon counters is getting measurably more difficult. At least once a week an online tool to calculate one's carbon footprint, based on self-reported energy consumption, is introduced or improved.Sun Microsystems, which participated in last month's Net Impact Conference, at the Wharton School of Business, says it recently tuned up its OpenEco.org, a site offering free tools to help participants measure, track, and compare energy and greenhouse gas (GHG) performance.

Hewlett-Packard on Wednesday introduced improvements to the HP Eco Solutions program with the launch of the new HP Eco Printing assessment service and new capabilities added to the HP Carbon Footprint Calculator. The HP Eco Printing assessment service helps calculate the current environmental impact of the imaging and printing fleet, develop a road map for reducing carbon footprint through changes in infrastructure, management, workflow and employee behavior, and quantify financial and environmental benefits of going green.

There also have been changes -- and because of its nature, it's pretty much undergoing constant change -- to AMEE, based in London. In case you're not familiar with it, AMEE is a Web-based service that combines measurement, calculation, profiling, and transactional systems to calculate energy-use into CO₂ emissions. The twist: It represents data from 150 countries.

Its humble goal? Its management explains:

"AMEE's aim is to map, measure, and track all the energy data on Earth. This includes aggregating every emission factor and methodology related to CO₂ and Energy Assessments (individuals, businesses, buildings, products, supply chains, countries, etc.), and all the consumption data (fuel, water, waste, quantitative and qualitative factors).

AMEE's recent change is planned support for PAS 2050, a new carbon-measurement standard now being piloted by consumer-products manufacturers. Launched by BSI British Standards, the Department for the Environment, Food and Rural Affairs (Defra/DEC) and the Carbon Trust, it is being used by Tesco, Cadbury, and more than 70 other companies.