energy credit

The credit for energy efficient windows is limited to only $200.

IRS Form 5695,Residential Energy Credits instructions, page 2 - https://www.irs.gov/pub/irs-prior/i5695--2018.pdf

Nonbusiness Energy Property Credit (Part II)
You may be able to take a credit equal to the sum of:
1. 10% of the amount paid or incurred for qualified energy efficiency improvements installed during 2018, and
2. Any residential energy property costs paid or incurred in 2018.
However, this credit is limited as follows.
• A total combined credit limit of $500 for all tax years after 2005.
• A combined credit limit of $200 for windows for all tax years after 2005.
• A credit limit for residential energy property costs for 2018 of $50 for any advanced main air circulating fan; $150 for any qualified natural gas, propane, or oil furnace or hot water boiler; and $300 for any item of energy efficient building property.