Can a solar water heating system be considered a renewable energy system?

Yes solar hot water systems are considered renewable energy systems and contribute toward this credit.

Hi Engr. Marcus, As stated in the LEED v4 Reference Guide, Further Explanation, Eligible Renewable Energy Systems:   “Allowable sources for renewable energy include the following:

• Solar thermal” this confirms it. But i wanted to know how to calculate this credit?

The energy savings needs to be estimated by your modeling software or another method. You can find solar hot water system calculators online which should be acceptable because hot water loads do not have any interactive effects with other building systems (any that do can't be modeled or estimated separately). Typically these systems are sized for about 80% of the hot water load (getting to 100% requires a very large number of additional collectors), so your savings should reflect something close to this percent savings. FYI I am not an engineer.

Yes, a solar water heating system is considered a renewable energy system. It harnesses energy from the sun, which is a renewable resource. Installing a solar water heating system can help with renewable energy credits, such as those offered by various government programs and green building certifications. This system reduces reliance on non-renewable energy sources and lowers greenhouse gas emissions, contributing positively to sustainability goals. If you're looking to qualify for specific credits, check the requirements of the particular program you're interested in, as they may have specific criteria for the type and efficiency of the system.