Luyện nói tiếng Anh bằng Shadowing qua video: Is Solar About to Get WAY Better? (I Did the Math)
Chọn chế độ luyện tập
Mỗi chế độ mở một phòng luyện tập toàn màn hình.
215 câu
Nếu các câu quá ngắn hoặc quá dài, hãy bấm Edit để chỉnh sửa.
1
Perovskite solar cells could hit 35% efficiency and cost half as much as silicon.
2
But they're still years away from your roof.
3
Meanwhile, silicon panels just lost their 30% federal tax credit here in the US, making them suddenly more expensive.
4
So here's the $20,000 question.
5
What's the better path in value?
6
Should you wait for the next solar breakthrough technology to finally arrive?
7
Or install silicon solar panels right now?
8
Which gives you the better bang for your buck?
9
I'm Matt Farrell.
10
Welcome to Undecided.
11
This video is brought to you by 8sleep.
12
I get asked about solar a lot.
13
People send me their quotes, their roof diagrams, their utility bills.
14
But the question that comes up more than any other.. should I wait?
15
Wait for the next breakthrough.
16
Wait for the prices to drop.
17
Wait for the technology to get better.
18
I've installed solar on two different homes now, so I've gone through this decision myself.
19
And here's the thing.
20
That question never really goes away.
21
There's always something newer on the horizon.
22
So let's figure out if waiting actually makes sense.
23
And to figure that out, we need to understand the technologies that we're considering.
24
Today's silicon sells versus next-gen options like perovskite.
25
When I say the word solar panel, you're almost certainly picturing silicon photovoltaics, or PV.
26
That's for a good reason.
27
They're pretty much everywhere nowadays.
28
I've got 43 of them on the roof of my home, plus 4 more on a shed in the backyard.
29
Silicon is very common on Earth.
30
It's actually one of the most abundant elements and it's pretty cost efficient and effective as a photovoltaic material.
31
Perovskite PVs work in very similar fashions to silicon PVs.
32
From installation, purchasing and appearance, there's no difference.
33
The big difference is their tunable band gap.
34
So think of it like this.
35
Every solar material has a sweet spot for converting light into electricity.
36
Silicon is stuck at one setting.
37
But perovskites can be tuned to match different conditions, which is why they can be so much more efficient.
38
I've got videos that go into more detail if you're interested that I'll link to in the description.
39
The tunability of perovskites also unlocks the power of tandem solar cells.
40
We can tune the perovskites to eat a different wavelength of light from what the silicon can.
41
A light in the range of 380 to 700 nanometers slams into the perovskite and works through that system as normal.
42
But near infrared light at wavelengths of about 800 to 2500 pierces through the perovskites.
43
that would just be lost, but a layer of silicon behind the perovskite can absorb it.
44
By working in, well, tandem, the solar cells duo can let us double dip and extract more energy from that same beam of light.
45
They can hit conversion efficiencies of near 35%, which is much better than silicon or perovskite on their own.
46
One final thing before we get into the nitty gritty of the math.
47
All of the advantages of perovskites come with some drawbacks.
48
Perovskites are temperamental little crystals that degrade when exposed to moisture, heat, and prolonged UV radiation.
49
That's a big problem for any device that's meant to soak up the sun, especially if it wants to compete with that 25 plus year longevity of the humble silicon cell.
50
Overcoming this challenge has been at the forefront of perovskite research.
51
A few companies like Oxford PV have claimed
52
that they've conquered this with tandem PVs that are durable enough to compete with silicon and are already commercially deployed.
53
The current crop of tandem cells have more modest efficiencies, around 25%, but are expected hit 30% within a few years.
54
That's why it's really sparking this whole debate of get solar now or wait.
55
Given Perovskite's advantages, you might think this is settled.
56
Before we do the math though, I want to talk about something else that's got me all heated up and then cooled right back down again.
57
That's today's sponsor, 8Sleep.
58
I love it warm.
59
Like, climb into a toasty bed, heavy blanket.
60
This is the best part of my day warm.
61
But I also can't sleep hot.
62
The moment I'm actually asleep, I want it cool.
63
My wife thinks I'm a nightmare.
64
And she's not wrong.
65
Which is why I've been using 8 Sleep since it was a Kickstarter project.
66
Seriously, I've been using it since the original version.
67
And the Pod 5 is what that idea has grown into.
68
The Pod sits right on top of your existing mattress.
69
It warms up when I get in, exactly how I like it, then it cools back down as the night goes on.
70
My wife runs her side completely different.
71
Same bed, totally separate temperatures.
72
We've never thought about the thermostat since.
73
But the real reason I keep coming back to it?
74
The sleep quality.
75
I travel a fair amount and I feel the difference every single time I'm away from home.
76
My deep sleep drops.
77
I wake up feeling foggy and not well rested.
78
Coming home to the pod is genuinely one of the highlights of getting back.
79
8sleep's autopilot learns from your patterns and automatically adjusts temperature throughout the night.
80
It also tracks your sleep stages, heart rate variability and more.
81
No wearables needed.
82
The best part is that you still get 30 days to try it in your home
83
and return it if you don't like it.
84
but I'm confident you're going to love it.
85
Trust me, your body will thank you for this investment in better sleep.
86
Use my code MATT at 8sleep.com slash Matt Ferrell for up to $350 off the Pod5 Ultra.
87
Thanks to 8sleep and to all of you for supporting the channel.
88
Alright, back to the math.
89
So should you wait for Solar 3.0 or go with reliable silicon?
90
A quick caveat, I'm working with US dollars here with average pricing, so there's going to be some generalizations.
91
There There are tons of variables here.
92
Your situation is going to be very different.
93
Ok, what's our baseline?
94
Let's go with a 6kW system.
95
It's on the smaller end and should fit most roofs.
96
It's large enough to see a real change in your bills.
97
The average cost of installing a 6kW system in the United States is $15,900.
98
That includes labor, panels, permits, and local rebates.
99
A system of this size will save about $1500 annually on your electric bill.
100
Obviously, this depends on how much electricity you use and how much energy your PVs produce.
101
But again, we have to deal in averages here.
102
How long will it last?
103
The well-documented answer is 20-30 years.
104
To keep things simple, let's just say 25 years.
105
Here's the math.
106
$1,500 for 25 years is $37,500 in lifetime savings.
107
Subtract your install costs of $15,900 from that and you get the real savings of $21,600 on average.
108
It's not too shabby.
109
For payback, divide 15,900 by 1,500 annual savings.
110
That's 10.6 years, which is roughly half the system's lifetime.
111
It's actually better than that for most people, but we'll just let that go for now.
112
I think just about anyone would be happy with the numbers we've got here, but they could be better.
113
Location matters.
114
A 6 kilowatt system in Phoenix, Arizona, known monument to man's arrogance,
115
will generate around 35% more electricity than that same system near me in Boston.
116
And while the federal tax credit ended on January 1st, your city, state or neighborhood may offer rebates.
117
In markets like Australia, with better incentives and more sun, that same 6kW system costs around $4,300 and saves even more.
118
So what about the next-gen technologies?
119
What kind of cost savings are you looking at for perovskite tandem cells?
120
Let's do our best to figure it out.
121
I want to be very clear here, we're working with the best information available at the moment.
122
And while some companies are targeting earlier release dates for residential markets like 2028,
123
the current consensus prediction is that commercial residential perovskites won't become a mainstream option until like 2030.
124
A lot can change even in a couple years and we could be way off, but to make things fair for materials and easier on us,
125
let's assume that the installation cost for perovskite tandem cells is the exact same as silicon.
126
It really should be.
127
Also to keep everything square, we'll assume that we're going for a 6 kilowatt system again.
128
So how much does a 6 kilowatts of perovskite tandem cells cost?
129
Techno-economic analysis from the National Renewable Energy Lab suggests that American-made,
130
25% efficient tandem panels could be as cheap as $0.29 to $0.42 per watt.
131
This does assume that we can manufacture them at gigawatt scale factories, which I think is unlikely to happen by 2028 or maybe even 2030.
132
We'll just roll with it for now and say that it's $0.35 per watt.
133
But that's just the manufacturing cost, which is only about 12% of the total installation cost.
134
To figure out how much it costs the consumer, we also have to work out how much it will cost to install per watt.
135
That includes stuff like labor, shipping, the racks and rails that will attach to the roof, and you get the idea.
136
So let's try to flatten some variables and assume the cost is identical to silicon.
137
In 2026, silicon modules look to be around 21 cents per watt.
138
Plugging that into our calculations for a 6kW silicon system, 12% of 15,900 is equal to $1,908.
139
Meaning everything outside of the manufacturing costs is $13,992.
140
So at $0.35 per watt, the manufacturing cost of 6kW of panels would be $2,100.
141
Add the $13,992 back in and theoretically that means a 6kW perovskite system would run you about $16,092.
142
That's not all that different.
143
The bigger your system, the more the manufacturing cost difference adds up.
144
But that's the upfront cost.
145
How much will perovskite systems save you over time?
146
Oxford PV offers the most solid numbers here.
147
Their modules hit a reported 26.9% efficiency.
148
That's ahead of silicon's 20-24% range.
149
Oxford is targeting 30% by 2030, but let's use today's conservative numbers.
150
For our comparison, we'll assume 22% efficient silicon panels and keep everything else identical.
151
At 26.9% efficiency compared to 22% for silicon, a perovskite tandem system is about 22.3% more efficient.
152
With that 22.3% efficiency boost, perovskite saves you an extra $335 annually.
153
That's $1,835 per year total.
154
But perovskites don't last as long as silicon.
155
Silicon currently max out around 15 years, though many companies are targeting 20 years by 2028.
156
At 20 years, you're looking at a lifetime savings of about $36,690.
157
Subtract the $16,092 for the install costs and you get the real savings of $20,600.
158
That's worse than silicon's $21,600.
159
If perovskites stay stuck at 15 years, it gets worse.
160
However, if they match silicon's 25 year lifespan, that extra $335 per year adds up to over $8,000 more than silicon.
161
Payback period is 8.8 years regardless.
162
About 2 years faster than silicon.
163
So is that the final word?
164
Victory to Silicon?
165
No. As we've mentioned before, I tried to make the math as general and simple as possible, so that we could get a handle on the situation.
166
However, there's a lot of variables and caveats that we have to consider.
167
Location matters.
168
A lot.
169
Sunnier places will outperform temperate regions like New England.
170
Panel direction matters too.
171
In the Northern Hemisphere, they generally face south, but if that side of your roof is shaded or limited, your output suffers.
172
On the financial side, there's also incentives.
173
While the federal tax credit just ended, your state or city might offer rebates.
174
Again, I point to Australia, where friendlier incentives, policies, and a different level of tech maturity lets residents of even
175
Australia's most expensive states install rooftop solar for cheaper than the cheapest American states.
176
And the flip side of incentives are tariffs.
177
Current tariffs on China and Southeast Asia affect most silicon panels on the US market, but not elsewhere.
178
Whether those tariffs help or hurt perovskites depends on where they're manufactured and who's buying.
179
When it comes to perovskites, there's still a lot of unknowns.
180
I've made assumptions about costs and performance.
181
By the time they actually hit the mass scale, the market could shift and throw our calculations just way off.
182
In fact, they probably will.
183
There's no guarantee that the first generation will be as cheap or efficient as expected, or as cheap as the second and third generations.
184
The biggest factor is opportunity costs silicon installs take 1-3 days.
185
Perovskites?
186
The current consensus is that we're not expected to see residential commercial perovskites hit in a meaningful way until 2030.
187
Oxford PV is targeting 2028, while conservative estimates say that it's 2035.
188
That's years of lost savings while you wait.
189
So what should you do?
190
Here's my take.
191
If you want to save money, be greener, or more energy resilient, whatever your personal motivation may be, don't wait.
192
I've installed silicon panels twice and I have zero regrets.
193
Even after moving after just 5 years.
194
Silicon works.
195
It's proven.
196
You can get it installed relatively quickly and start saving immediately.
197
If it doesn't make financial sense right now, that's fine too.
198
Prices keep dropping for both technologies.
199
But if you can swing it?
200
The math says go now.
201
Every month that you wait is a month of lost savings.
202
So while the next generation of solar technology is exciting, I wouldn't wait.
203
But what do you think?
204
Do you want to wait for the next-gen solar to arrive?
205
If so, why?
206
Jump into the comments and let me know.
207
You can also check out my extended cuts of my videos over on Patreon.
208
And speaking of that, these videos take a team to make.
209
A team of humans with real research, real interviews, real feedback from experts.
210
No AI slop.
211
If that matters to you, Patreon support helps a ton.
212
The link's in the description if you'd like to join, but honestly, just watching like you are right now is awesome.
213
So thank you.
214
And check out my follow up podcast, still to be determined we'll keep this conversation going.
215
Keep your mind open, stay curious, and I'll see you in the next one.
Tải Ứng Dụng
Mọi thứ bạn cần để nói trôi chảy
Chấm điểm AIChấm từng câu nói
Luyện IPAThành thạo mọi âm
Từ vựngMở rộng vốn từ
Game Từ vựngHọc qua chơi
Cùng kênh
C18
How Quantum Batteries Break Every Rule of Charging
Daily ConversationUniversity StudentsWorking Adults
C11
The Hidden Problem With Home Batteries
Daily ConversationWorking Adults
B22
How Solar Is Beating Nuclear's Best Idea
Daily ConversationUniversity StudentsWorking Adults
B23
How the Worst Oil Crisis in History is Backfiring
Business EnglishDaily ConversationUniversity Students
B28
Why Australia’s Solar Is So Cheap (And Ours Isn’t)
Business EnglishDaily ConversationUniversity Students
B28
The Truth About Ocean Plastic
IELTS PrepTOEFL PrepUniversity Students
FOR YOU
Video gợi ý
B2435 câu
Color Palettes Worth Another Look
Business EnglishDaily ConversationUniversity Students
B24
180 câu
Is AI Doom Real... or Just Good Marketing?
Business EnglishUniversity StudentsWorking Adults
B21
157 câu
Basic Solar Components & How They Work - Solar Panels, Inverter, Batteries, & More Explained (Ep. 2)
Business EnglishUniversity StudentsWorking Adults
B21
11 câu
iPhone 17 Pro Max Review - 6 Months Later
Business EnglishUniversity StudentsWorking Adults
C13
169 câu
It Sucks for 3 Days But It Makes Waking Up Early Effortless - Dr Andrew Huberman
Business EnglishUniversity StudentsWorking Adults
B23
51 câu
Great Moments in Unintended Consequences: Yosemite Permits, Italy Superbonus, Salary Caps (Vol. 22)
Business EnglishDaily ConversationUniversity Students
B24
167 câu
5 Stages to Getting Rich in 2026: Which One Are You?
Business EnglishUniversity StudentsWorking Adults
C12
133 câu
Carbon Fiber - The Material Of The Future?
Business EnglishUniversity StudentsWorking Adults
B22
243 câu
I might have found the BEST budget router...
Business EnglishUniversity StudentsWorking Adults
B131 câu
$182 Skinceuticals vs. $16 e.l.f. Vitamin C Serum (is it a dupe??)
Business EnglishDaily ConversationUniversity Students
B22
67 câu
How Agri-Voltaics are Changing Agriculture | The Power of Solar Panels | EyeTech
Daily ConversationUniversity StudentsWorking Adults
Từ vựng và ghi chú luyện nói cho bài học này
Video này có 215 câu và 2317 từ để luyện shadowing. Phần lời nói dài 13:11. Người nói nói với tốc độ tự nhiên, khoảng 176 từ mỗi phút, gần với hội thoại hằng ngày. Chỉ 80% số từ nằm trong 3.000 từ tiếng Anh thông dụng nhất, nên từ vựng khá khó.
Từ vựng quan trọng trong video
15 từ đáng học trong video, kèm phiên âm và nghĩa:
| Từ | Phiên âm | Nghĩa |
|---|---|---|
| silicon danh từ | /ˈsɪləˌkɑn/ | silic |
| install động từ | /ɪnˈstɔl/ | cài đặt |
| mathematics danh từ | /mæθ(.ə)ˈmæt.ɪks/ | toán học |
| watt danh từ | /wɑt/ | watt, oát |
| arrive động từ | /əˈɹaɪv/ | đến |
| tune danh từ | /tjuːn/ | điệu nhạc, âm điệu |
| identical tính từ | /ɪˈdɛntɪkl̩/ | hệt, y hệt |
| consensus danh từ | /kənˈsɛnsəs/ | sự đồng lòng, sự đồng thuận |
| module danh từ | /ˈmɑd͡ʒul/ | mô-đun, bộ phận rời |
| calculation danh từ | /ˌkælkjuˈleɪʃn̩/ | tính toán |
| curious tính từ | /ˈkjʊɹ.i.əs/ | tò mò |
| suffer động từ | /ˈsʌfɚ/ | chịu đựng |
| guarantee danh từ | /ˌɡæɹ.ənˈtiː/ | sự bảo đảm |
| output danh từ | /ˈaʊtpʊt/ | đầu ra |
| crystal danh từ | /ˈkɹɪstəl/ | tinh thể, pha lê |
Cụm động từ bạn sẽ nghe
| Từ | Phiên âm | Nghĩa |
|---|---|---|
| check out động từ | tính tiền, trả phòng | |
| wake up động từ | /ˌweɪk ˈʌp/ | thức dậy, dậy lên |
Phát âm cần chú ý
Người nói dùng 44 dạng rút gọn, ví dụ I've, I'm, we'll. Hãy nói theo dạng ngắn đúng như bạn nghe.
- Âm “th”: mathematics /mæθ(.ə)ˈmæt.ɪks/, breakthrough /ˈbɹeɪk.θɹuː/, wavelength /ˈweɪvˌlɛŋ(k)θ/, thermostat /ˈθɝməstæt/
- Âm “sh” và “zh”: efficient /ɪˈfɪʃənt/, efficiency /ɪˈfɪʃ.ən.si/, residential /ˌrɛzɪˈdɛnʃəl/, installation /ˌɪn.stəˈleɪ.ʃən/, calculation /ˌkælkjuˈleɪʃn̩/
- Từ dài — đặt trọng âm cho đúng: efficiency /ɪˈfɪʃ.ən.si/, mathematics /mæθ(.ə)ˈmæt.ɪks/, electricity /ɪˌlɛkˈtɹɪsɪti/, residential /ˌrɛzɪˈdɛnʃəl/, installation /ˌɪn.stəˈleɪ.ʃən/
Cách luyện với video này
- Nghe hết video một lần, chưa cần nói, và ghi lại những từ bạn chưa biết.
- Bắt đầu ở tốc độ 0,75×, nói đuổi từng câu, rồi quay lại tốc độ bình thường khi đã quen.
- Ghi âm giọng mình rồi so với bản gốc, chú ý các từ như silicon, install, mathematics.
Ngữ pháp trong video
Những cấu trúc người nói dùng nhiều nhất, kèm đúng cụm từ trong video:
| Cấu trúc | Trong video |
|---|---|
| Thì hiện tại hoàn thành tiếp diễn have/has been + -ing — việc bắt đầu từ trước và vẫn đang tiếp tục | I've been using |
| Thì hiện tại hoàn thành have/has + quá khứ phân từ — việc đã xảy ra nhưng còn liên quan đến hiện tại | I've installed · has been · have claimed |
| Câu bị động be + quá khứ phân từ — nhấn vào việc xảy ra, không phải người làm | is brought · can be tuned · be lost |
| Mệnh đề quan hệ who / which + mệnh đề — thêm thông tin về người hoặc vật | conditions, which is · years, which is · cost, which is |
Phương Pháp Shadowing Là Gì?
Shadowing là kỹ thuật học ngôn ngữ có cơ sở khoa học, ban đầu được phát triển cho chương trình đào tạo phiên dịch viên chuyên nghiệp và được phổ biến rộng rãi bởi nhà đa ngôn ngữ học Dr. Alexander Arguelles. Nguyên lý cốt lõi đơn giản nhưng cực kỳ hiệu quả: bạn nghe tiếng Anh của người bản xứ và lặp lại to ngay lập tức — như một "cái bóng" (shadow) đuổi theo người nói với độ trễ chỉ 1–2 giây. Khác với luyện ngữ pháp hay học từ vựng bị động, Shadowing buộc não bộ và cơ miệng phải đồng thời xử lý và tái tạo ngôn ngữ thực tế. Các nghiên cứu khoa học xác nhận phương pháp này cải thiện đáng kể phát âm, ngữ điệu, nhịp điệu, nối âm, kỹ năng nghe và độ lưu loát khi nói — đặc biệt hiệu quả cho người luyện IELTS Speaking và muốn giao tiếp tiếng Anh tự nhiên như người bản ngữ.