The greenhouse in Chen Xin's shelter is not large, only one hundred square meters, which is equivalent to one are, one-sixth of a mu of land.
Here, Chen Xin actually made a mistake. When the construction team asked him how large he wanted the greenhouse to be, he miscalculated an are as a mu, resulting in the greenhouse being six times smaller than intended.
In Chen Xin's original plan, this space was meant for growing upland rice and vegetables, providing him with food for his own consumption and for trading for other resources.
However, due to the calculation error, the output is far from sufficient.
The annual yield of upland rice is about nine hundred jin per mu, and the yield of rice after husking is about seven hundred jin, while one are is only about one-sixth of a mu of land, producing only a little over a hundred jin.
An adult consumes about three hundred jin of rice annually, in addition to an equivalent amount of vegetables and meat. Simply put, if Chen Xin wants to maintain a healthy state, he would need to consume at least five to six hundred jin of food per year.
Considering that future surface temperatures will drop to minus several tens of degrees, sufficient food is crucial for energy supply, and food consumption would likely be more rather than less.
In the limited conditions of the post-apocalypse, Chen Xin no longer counts on meat, but even just with vegetables and rice, the one hundred square meter greenhouse can yield at most three hundred jin of rice annually, even with two seasons of upland rice, with no room left for vegetables.
Three hundred jin of rice is by no means enough to meet Chen Xin's annual food needs.
Originally, Chen Xin planned to grow half a mu of upland rice to ensure his food supply, with the other half growing vegetables like carrots, cabbage, and lettuce, which would allow surplus to be traded at other shelters for resources.
After all, with the onset of the apocalypse, there would be no sunlight on the surface, and temperatures would fall to minus several tens of degrees. Cultivating crops and vegetables would entirely depend on these greenhouses.
Having a greenhouse to grow some grain and vegetables assures a certain level of life quality and food supply, allowing Chen Xin to survive on his own greenhouse when there are no other food sources.
Moreover, in apocalyptic times, if Chen Xin could have a stable channel for producing vegetables and fruits, it would be a very reliable source of income in the near future.
By then, it would be very feasible to exchange fresh vegetables for other grains and resources, or even gasoline needed for power generation.
Just like in "Wandering Earth" where people eat dried worms and similar foods, presenting fresh vegetables and fruits would definitely trade for many good things.
In Chen Xin's initial plan, this mu of land was meant to be half for growing upland rice and half for vegetables and fruits, meeting his consumption and leaving some for trading.
But due to his calculation error, having confused an are with a mu, the yield was only one-sixth of the original plan, insufficient to meet his consumption, let alone have surplus for trade.
Chen Xin has carefully calculated that to meet his annual food consumption, the greenhouse area must be at least doubled. To have surplus production for trade requires an area at least three to four times its current size.
Initially, it seemed impossible for Chen Xin to expand the greenhouse. Though not a container house, the greenhouse walls were insulated, and cement was poured, so expansion would mean knocking down a wall and digging with a spade himself.
While there was nothing else to do in the shelter, digging out a hundred square meters of greenhouse would take at least one or two months.
As for subsequent wall insulation and such, not to mention that he didn't even have the construction materials.
However, now with the system, everything is entirely different.
"Simple Greenhouse"
"Upgrade Plan One: Add a drip irrigation system and hydroponic planting trays, increase crop yield by 10%, reduce irrigation water by 10%, survival points required for upgrade: 2000."
"Upgrade Plan Two: Increase planting area, enhance the efficiency of supplementary lighting, increase crop yield by 10%, reduce lighting duration by 10%, survival points required for upgrade: 3500."
The two upgrade plans differ, but both can expand the greenhouse planting area.
The first plan adds hydroponic planting trays suspended in the air, effectively turning the original one hundred square meter greenhouse into two levels, with upland rice on the lower level and vegetables on the upper hydroponic trays, coupled with a 10% crop yield increase from the upgrade, which would sufficiently meet Chen Xin's food consumption.
As for the second plan, it aligns with Chen Xin's original idea, to knock out a wall and expand the entire greenhouse, increasing the area from one hundred square meters to two hundred square meters, which would also meet Chen Xin's personal consumption needs, though the space utilization rate is evidently lower than the first plan.
Moreover, the first plan also includes the addition of a drip irrigation system, the most water-efficient irrigation method, achieving a 95% water resource utilization rate, initially used for arid region irrigation, and for Chen Xin, who will find it challenging to obtain water resources in the future apocalypse, this method can certainly save him a lot of water that would otherwise be consumed.
Nevertheless, the enhancement of the lighting efficiency in the second upgrade plan also garnered some of Chen Xin's interest.
Supplementary lights are devices used to simulate sunlight, essential for greenhouse planting to compensate for plant lighting needs.
As lighting conditions can often be suboptimal, affecting plant growth, this is especially true for cultivating some precious or delicate plants, with different lighting time requirements at different growth stages, necessitating supplementary lights to make up for lighting time.
Chen Xin has installed four supplementary lights in the greenhouse, running twelve hours a day to fully replace natural sunlight, reducing lighting time by an hour can save a considerable amount of electrical energy.
While the small current area doesn't reveal this saving effect, expanding the planting area and increasing the number of supplementary lights would significantly enhance this energy-saving effect.
But at present, Chen Xin is still accumulating ten survival points a day, unable to afford two or three thousand survival points to upgrade the greenhouse without sufficient savings.
Therefore, Chen Xin can only make an upgrade plan based on the importance and cost of upgrading different rooms, estimating that it may take at least a year to truly upgrade these rooms.
Of course, if Chen Xin chooses to upgrade certain equipment or items instead of the entire room, accumulating for about a month would be almost enough for one upgrade.
However, considering the cost-performance ratio, Chen Xin still doesn't want to proceed with upgrading individual items.