CHP案例研究：真实设施中的热电联产

The site

A 一个 12,000 平方米、含医院翼楼、泳池与办公区的区域，全年热需求稳定且电网电价高昂。为此安装了 500 kWe 天然气 CHP 机组，以提供基础负荷电力并回收缸套与排气余热，用于空间供暖和生活热水。

What it recovered

• 电力输出：连续 500 kWe。
• 回收热量：约 650 kWth，水温 80–90℃。
• 燃料总效率：约 85%，而单独电网供电仅约 40%。

Where HVAC recovery helped

CHP 覆盖了高温水回路，但建筑仍在排放已处理空气。增设 板式空气-空气换热器 在通风侧回收了剩余的低温排气，补充了我们在 CHP 概述.

Results

• 现场 CO2 降低约 28%。
• 能源成本降低约 22%。
• 简单回收期：4.5 年。

Lessons

CHP pays only when heat demand is continuous and matches engine output – oversizing wastes the advantage. Validate with a 投资回收期计算 并查看 废热回收基础 以了解完整的热阶梯。

Operating the combined system

In practice the CHP engine and the plate air-to-air exchangers operate on different loops but share a goal: extract value from every grade of heat. The CHP satisfies the steady high-grade demand for space heating and hot water, while the ventilation-side plates trim the low-grade exhaust losses that the engine cannot reach. Coordinating their control avoids the CHP exporting heat the building cannot use at that moment.

Lessons on matching output

The case reinforces a core CHP rule: the engine must be sized to the continuous heat demand, not the peak. An oversized unit spends part of the year dumping heat or throttling, erasing the efficiency gain. The 4.5-year payback assumed a well-matched load profile and steady operation, which is why a payback calculation belongs in the feasibility stage, not after installation.

Measuring the result

The reported 22 percent energy-cost and 28 percent CO2 reductions came from comparing metered site performance against the pre-CHP baseline, including the ventilation recovery contribution. Tracking both the water-loop and air-side savings separately keeps the business case transparent and shows where further trimming, better control or wider recovery coverage, is still possible.

常见问题

What did the CHP case study recover?
A 500 kWe engine plus about 650 kWth at 80 to 90C water, lifting total fuel efficiency to about 85 percent versus roughly 40 percent for grid power alone.

How did HVAC recovery help the CHP site?
Plate air-to-air exchangers captured the low-grade ventilation exhaust that the water loop could not reach, complementing the CHP.

What were the reported results?
Site CO2 fell about 28 percent, energy cost about 22 percent, with a simple payback of 4.5 years.

What is the key CHP lesson?
Size the engine to the continuous, matched heat demand. Oversizing that dumps heat wastes the advantage. Validate with a payback calculation.

常见问题

What did the CHP case study recover?

A 500 kWe engine plus about 650 kWth at 80 to 90C water, lifting total fuel efficiency to about 85 percent versus roughly 40 percent for grid power alone.

How did HVAC recovery help the CHP site?

Plate air-to-air exchangers captured the low-grade ventilation exhaust that the water loop could not reach, complementing the CHP.

What were the reported results?

Site CO2 fell about 28 percent, energy cost about 22 percent, with a simple payback of 4.5 years.

What is the key CHP lesson?

Size the engine to the continuous, matched heat demand. Oversizing that dumps heat wastes the advantage. Validate with a payback calculation.