2016 Volume 12 Issue 3 Pages 170-179
Japan has a national goal of reducing greenhouse gas emissions in 2030 to 26% below 2013 levels. Energy efficiency improvement and low carbon power generation technologies will provide the primary source of greenhouse gas reductions. On the other hand, the feed-in tariff(FIT)program that began in 2013 triggered explosive growth of renewable power sources, particularly photovoltaic generations because of its short lead-time and high tariff level. However, mass introduction of renewable power sources causes serious instability issues in power systems. One of these issues is that the mass introduction impacts to the transient stability in power systems. Since it could lead to a massive blackout in the worst case, the power system must be very carefully managed to maintain the transient stability. Another issue is that outputs of photovoltaic and wind power generations fluctuate, causing frequency instability. These fluctuations must be absorbed so as to keep stable frequency in each power system, which is called LFC, load frequency control. Issues on LFC are omitted in this article due to the page limit. In this article, we introduced the constraints on the transient stability in the power generation mix in Kyushu region, taking massive installation of photovoltaic systems into consideration. Next we described on our mathematical model of economic load dispatch for Kyusyu district, taking transient stability into consideration. Computed results quantified suppression of photovoltaic generation in each primary grid, and indicated that the suppression concentrated on specific power transmission lines. Furthermore we investigated the way to efficiently utilize the suppressed power, including estimation of economic feasibility to produce hydrogen utilizing electrolysis.