How to calculate the energy consumption of ULPA operation?

Let me start with a confusing point: ULPA itself does not consume electricity. It has no motor, no control system, it is just a filter. The so-called 'ULPA operating energy consumption' actually refers to the impact of filter element resistance on the power of the air supply system.。

After understanding this, the calculation logic becomes clear: as the filter element resistance increases, the fan needs to provide higher static pressure to maintain the same air volume, and the input power changes accordingly. How much it changes depends on the variables of air volume, pressure loss, fan efficiency and operating hours.

What are the inputs to the calculation?

The starting point for energy consumption estimation is to clarify several basic parameters.

Air volume. How much air supply volume does the system need to maintain? Whether the unit is cubic meters per second (m³/s) or cubic meters per hour (m³/h), the calculation must be consistent.

System pressure loss. Including filter element resistance, pre-filtration resistance, air duct resistance, box resistance and end resistance. It should be noted that when calculating the change in energy consumption caused by the filter element, only the difference in the resistance of the filter element should be compared, and do not include the resistance of all links.

Fan and motor efficiency. There is a gap between the air power of the fan and the actual input power. This gap is determined by fan efficiency, motor efficiency and transmission efficiency. The specific value should come from the fan performance curve and equipment data, and cannot be estimated based on experience.

Run time. Number of hours in each operating mode throughout the year. The time ratio between working mode and duty mode is different, and the energy consumption difference is also different.

Air power can be estimated with a simplified formula: air volume (m³/s) multiplied by pressure difference (Pa), the result is watts (W). This is the theoretical air power, and the actual input power is divided by the efficiency of the fan and motor.

Keep the same target when comparing

When comparing energy consumption in upgrading and renovation projects, the most common problem is inconsistent goals.

Comparisons should be made under the same air supply demand before and after the upgrade. If the air volume changes after replacing the filter element, then part of the power difference comes from the change in air volume and cannot be entirely attributed to the filter element resistance.

Record the measured power in each mode. If the equipment has different operating gears, measure and record the power of each gear separately. The annual energy consumption is the power of each mode multiplied by the corresponding number of hours, and then summed.

The initial resistance and working conditions after dust accumulation are evaluated separately. The resistance of the new filter element is the lowest when it is first installed, and the resistance increases after running for a period of time. If the annual energy consumption is calculated only based on the initial resistance, the result may be low. A more realistic approach is to estimate based on the resistance change curve during the operating cycle, or calculate based on the average resistance.

Supporting For the FFU fan filter unit system, the unit itself has a speed adjustment function, and the energy consumption calculation also needs to consider the control strategy - under constant air volume control, when the resistance increases, the rotation speed will automatically increase, and the power will also change accordingly. For specific calculation methods, please refer to the relevant instructions on the resistance curve.

How to compare before and after the upgrade

The energy consumption comparison of upgrading from HEPA to ULPA is as follows.

The first step: test the operating data of the original system. Record the current air volume, fan gear, input power and filter element pressure difference. This set of data is the baseline before the upgrade.

Step 2: Obtain the resistance data of the new filter element. Ask the supplier for the initial resistance and final resistance data of ULPA under the target air volume. It is best to have a complete resistance curve. involving ULPA ultra-high efficiency filters , please refer to the corresponding product page. For specifications of

Step 3: Estimate the power under new operating conditions. Put the resistance of the new filter element into the total resistance of the system, find the new operating point based on the fan curve, and then estimate the input power based on the same efficiency parameters.

Step 4: Calculate the difference in energy consumption throughout the year. Multiply the power difference of each mode by the corresponding operating hours to summarize the changes in energy consumption throughout the year. Multiply that by the electricity price to get the electricity bill difference.

Step 5: Include other costs. Procurement spreads, replacement frequency, and downtime costs should all be considered when making decisions. Don’t just look at the electricity bill.

Project judgment example

Suppose a certain FFU is originally equipped with H14 and is upgraded to U15. The input power of the original system is 120 W under the target air volume, and the resistance of the new filter element is about 25% higher than the original filter element.

According to the fan curve estimation, after the rotation speed required to maintain the same air volume increases, the input power may rise to about 140 W. If it operates for 8,000 hours throughout the year, a power difference of 20 W corresponds to approximately 160 kilowatt-hours more electricity consumption throughout the year.

This is the arithmetic result in the example, not the product promise value. Actual projects must be calculated based on measured data and actual operating modes of the equipment. If the electricity price is 1 yuan/kWh, the annual electricity bill difference is about 160 yuan. Only by comparing this number with the difference in purchase price of the filter element and the difference in replacement cycle can we judge whether the upgrade plan is economically reasonable.

Don’t advertise energy savings based on grade or resistance differences alone. Actual energy consumption changes are greatly affected by system conditions, and the performance of the same filter element may be different in different systems. Device-side applications such as The EFU equipment-side fan filter unit has a compact internal space and little room for air volume adjustment. The calculation needs to be based on actual working conditions.

Selection and Acceptance Checklist

About Aili Industrial’s energy consumption accounting cooperation

The basis of energy consumption accounting is accurate operating data and product parameters.

Aili Industrial's manufacturing system covers filters, motors, fans, control systems and complete machine assembly, and can provide HEPA/ULPA products of different grades and supporting air supply equipment. filter with FFU fan filter unit、When the EFU equipment-end fan filter unit is matched in the same system, the filter element resistance and fan operating point can be calculated together during the planning stage, and the energy consumption difference can be evaluated based on actual working conditions.

Providing the original system operating data, design air volume and available static pressure when inquiring will help confirm the transformation plan and energy consumption estimate. The specific energy consumption data is subject to actual project measurements or calculations, and no unfounded energy-saving commitments are made.