国内致密砂岩气开发项目经济评价和财税扶持政策研究

Economic evaluation on tight sandstone gas development projects in China and recommendation on fiscal and taxation support policies

我国致密砂岩气(以下简称致密气)资源丰富,鄂尔多斯盆地苏里格气田、四川盆地上三叠统须家河组气藏等均属于典型的致密气藏。近10年来,国内致密气实现了快速增储上产,但由于我国致密气藏一直被按照常规天然气藏进行管理,缺乏有效的财税扶持和政策支持,致密气持续增产潜力明显受到制约,以苏里格气田为代表的致密气开发项目也长期未能取得盈利,自2015年以来产量已出现稳中趋降的苗头。为此,提出致密气开发项目应采用新的经济评价方式:要结合开发生产的特点,核定产量递减率、单井经济寿命等关键参数,采用产量法计提折旧,并考虑气井增压生产和间歇开井导致操作成本上升等问题。采用新的经济评价方式所得的结果显示,苏里格气田致密气开发项目收益水平远低于企业资金成本水平。结论认为:为了支持国内致密气产业可持续发展,建议相关部门尽快出台增值税先征后退政策,将致密气产地省份非居民用天然气门站价格恢复到公平合理水平,同时给予财政补贴0.24元/m^3;或者在现行门站价格基础上直接给予财政补贴0.32元/m^3。扶持政策的实施将直接带来增量税费收入,基本不会增加财政负担,而且能够显著降低国内天然气的消费成本。

China is rich in tight sandstone gas resources（ ＂tight gas＂ for short）. For example, the Sulige Gasfield in the Ordos Basin and the Upper Triassic Xujiahe Fm gas reservoir in the Sichuan Basin are typical tight gas reservoirs. In the past decade, tight gas reserve and production both have increased rapidly in China, but tight gas reservoirs are always managed as conventional gas reservoirs without effective fiscal, taxation and policy supports. The potential of sustainable tight gas production increase is obviously restricted. The tight gas development projects represented by the Sulige Gasfield have failed to make profit for a long period, and especially tight gas production has presented a slight decline since 2015. In this paper, a new economic evaluation method was proposed for tight gas development projects. The new method was designed to verify the key parameters（e.g. production decline rate and single-well economic service life） depending on tight gas development and production characteristics, and perform the depreciation by using the production method. Furthermore, the possibility that the operation cost may rise due to pressure-boosting production and intermittent opening of gas wells is considered. The method was used for the tight gas development project of Sulige Gasfield, showing that its profit level is much lower than the enterprise＇s cost level of capital. In order to support a sustainable development of tight gas industry in China, it is recommended that relevant authorities issue value-added tax（VAT） refund policy as soon as possible. It is necessary to restore the non-resident gas gate price of the provinces where tight gas is produced to the fair and reasonable level in addition to the fiscal subsidy of RMB0.24 yuan/m^3, or offer the fiscal subsidy of RMB0.32 yuan/m^3 directly based on the on-going gate price. With these support policies, tax income is expected to rise directly, fiscal expenditure will not increase, and gas consumption cost in China will be significantly cut down.