1. Single gas boiler hot water system
If the calorific value of natural gas is 8500 × 88% = 7480 kcal, the gas consumption per day is: 4000000 ÷ 7480 ≈ 534.76m3.
If the local natural gas price is 3.7 yuan / M 3, the annual operation cost of the heat source equipment of the gas boiler hot water system is 534.76m3/day × 3.7 yuan / m3 × 365 days = 722193.38 yuan, and 7222000 yuan is counted.
2. Single electric boiler hot water system
The electric heating value is 860 kcal, and the actual heating value is 860 × 95% = 817, so the power consumption of electric boiler system is 4000000 ÷ 817 ≈ 4895.96kw · H.
The local electricity price is 1.1 yuan / kWh, so the electricity cost of the heat source equipment of the electric boiler hot water system of the project is about 4895.96kw · H / day × 365 days × 1.1 yuan / kWh ≈ 1965700 yuan. Compared with gas-fired boiler, the annual operation cost of electric boiler is 1243500 yuan more.
3. Separate solar system
If the electric heating value is 860 kcal, and the actual heating value is 860 × 95% = 817, the daily operation power consumption of solar energy using electric auxiliary system is 4000000 ÷ 817 ≈ 4895.96kw · H.
The local annual precipitation days are 120 days, which means that the annual electricity cost of heat source equipment of the project is 4895.96kw · H / day × 120 days × 1.1 yuan / degree ≈ 646300 yuan.
4. Separate air source heat pump system
The standard cop of the hot water unit is 4.3, the electric heating value is 860 kcal, and the actual heating value of the air source heat pump is 860 × 4.3 = 3698, so the annual operation electric charge of the unit is 4000000 ÷ 3698 × 365 days × 1.1 yuan / degree ≈ 434300 yuan.
5. Solar energy + air source heat pump
The total amount of hot water in the project is 100 tons. If Tianyang energy is used for heating in sunny days with zero energy consumption and air source heat pump is used for auxiliary heating in rainy days, the heating cost of the project is about 4000000 ÷ 3698 × 120 days × 1.1 yuan / degree ≈ 142800 yuan.
From the calculation point of view, the solar energy + air source heat pump multi energy combined system saves 579400 yuan / year compared with the independent use of gas boiler, 1822900 yuan / year compared with the electric boiler, 503500 yuan / year compared with the solar energy, and 291500 yuan / year compared with the air source heat pump, with the best comprehensive energy saving advantages.