Next Article in Journal
Effect of Hygrothermal Ageing on Tribological Behaviour of PTFE-Based Composites
Next Article in Special Issue
Film Thickness and Shape Evaluation in a Cam-Follower Line Contact with Digital Image Processing
Previous Article in Journal
On the Temperature and Lubricant Film Thickness Distribution in EHL Contacts with Arbitrary Entrainment
Open AccessArticle

Reduction of CO2 Emissions and Cost Analysis of Ultra-Low Viscosity Engine Oil

Graduate School of System Design and Management, Keio University, 4-1-1 Hiyoshi, Kohoku-ku, Yokohama 223-8526, Japan
*
Author to whom correspondence should be addressed.
Lubricants 2018, 6(4), 102; https://doi.org/10.3390/lubricants6040102
Received: 13 October 2018 / Revised: 10 November 2018 / Accepted: 14 November 2018 / Published: 18 November 2018
(This article belongs to the Special Issue Automotive Tribology)
This study is focused on the reduction of CO2 emissions and costs associated with ultra-low viscosity (ULV) engine oils for passenger vehicles. Specifically, the reduction in life cycle CO2 (LCCO2) emissions from lower-viscosity engine oil and the oil drain interval (ODI) extension were estimated taking into account both mineral engine oil and synthetic engine oil. Furthermore, the cost-effectiveness of ULV engine oils were investigated by performing base-stock cost analysis. When the volatility limit of the Noack test (American Society for testing and materials (ASTM) D5800) was set to 15 wt %, the results indicated that the lower limit of kinematic viscosity at 100 °C (KV100) for mineral engine oil (with Group-III base-stock) and synthetic engine oil (with polyalphaolefin (PAO) base-stock) were approximately 5.3 and 4.5 mm2/s, respectively. Compared to conventional 0W-16 mineral engine oil (KV100 6.2 mm2/s), the effect of reducing LCCO2 emissions on ULV mineral engine oil (ULV-Mineral, KV100 5.3 mm2/s) was estimated at 0.6%, considering 1.5–1.8 L gasoline engines in New European Driving Cycles (NEDC) mode. ULV-Mineral, which continues to use a mineral base-stock, is considered highly cost-effective since its cost is similar to the conventional 0W-16 mineral engine oil. On the other hand, compared with ULV-Mineral, the vehicle fuel efficiency improvement from the use of ULV synthetic engine oil (ULV-PAO, KV100 4.5 mm2/s) was estimated to be 0.5%. However, considering CO2 emissions during engine oil production, the reduction of LCCO2 emission from ULV-PAO compared with ULV-Mineral was estimated to be only 0.1% or less using 2030 standards (assuming a vehicle fuel efficiency of 66.5 g-CO2/km) when ODI is set equivalent (7500 km) to mineral engine oil. As a result, ULV-PAO’s cost-effectiveness, considering the cost increase of PAO base-stock, was found to be nominal. Contrariwise, when the characteristics of PAO base-stock with higher oxidation stability are used comparatively with the mineral base-stock while extending the ODI to 15,000 km, the effect of reducing LCCO2 emissions of ULV-PAO was estimated to be 0.7% in 2030, making ULV-PAO a competitive and cost-effective alternative. In other words, the popularization of synthetic engine oil toward 2030 will require the consideration of both viscosity reduction and ODI extension. View Full-Text
Keywords: engine oil; low viscosity; life cycle assessment; CO2 emissions; cost analysis engine oil; low viscosity; life cycle assessment; CO2 emissions; cost analysis
Show Figures

Graphical abstract

MDPI and ACS Style

Ishizaki, K.; Nakano, M. Reduction of CO2 Emissions and Cost Analysis of Ultra-Low Viscosity Engine Oil. Lubricants 2018, 6, 102.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop